Pinion Angle

[BB767]

For background, I have read most of the info posted here for pinion angle requirements so many times i think I have them memorized!

The problem seems to be my specific rear end mounting. It cannot be set higher than minus 1 degree (down). The transmission output shaft is also at negative 1 degree (down). I know this match is not good and out of limits according to everything I have read. Problem is, the "banana" bar is already set 1/16th inch away from the panhard brace, it cannot be set any further back (thus raising the Pinion angle). In addition, I have already shimmed up the transmission about an inch which is the length of the supplied bolts. I am hesitant to raise it too high and cause other unanticipated problems elsewhere. Will be in contact with FFR but wanted to see if others have had this problem and how they solved it. Thanks.

[karlos]

If using the convention that the slope of the drivetrain is measured going from front to rear, a component slopes downward if it is lower at the rear than the front. A component slopes upward when it is higher at the rear than it is in front. If both your transmission and your differential slope downward as described above, you should be looking at this:

http://thefactoryfiveforum.com/attachment.php?attachmentid=78312&d=1514582993


If this is the case, then your pinion angle is zero. Right where you want to be. However, the u-joint operating angles still need to be checked to confirm no more than 3-degrees at either end. You'll need to measure the driveshaft angle in order to check this. Use this handy online calculator once you have your measurements: http://spicerparts.com/calculators/driveline-operating-angle-calculator

Objective is to get the operating angles at each end to be 3-degrees or less, and the difference between them (the pinion angle) to be 1-degree or less.

This is what the online calculator returns if I plug in your numbers. Note that I had to guess on the driveshaft angle. When I was done messing with my car it measured 2.2-degrees, so I just used that as a placeholder. If these were your final numbers you'd be in pretty good shape. Pinion angle is zero, and the 3-degree max operating angle is only exceeded by 0.2-degrees. Don't forget to compensate for driveline squat that will occur under hard acceleration. You'll probably want some upward slope bias on the differential so that the pinion angle and the operating angles are within spec while under load.

Good luck!


http://thefactoryfiveforum.com/attachment.php?attachmentid=78313&d=1514583922

[Gromit]

Getting these angles right is important for so many reasons... Something I would be concerned about is the 1/16th inch clearance on the banana bar to pinion brace. the bushings on the rear end will flex more than 1/16th inch during acceleration and or braking. that would cause these 2 parts to hit. just my $.02
Chris

[GoDadGo]

BB767,

I had the same issue, but mine was self-inflicted, because of the way that I set my engine and transmission which tilts down a couple of degrees toward the rear of the car.

Overview of Driveline:
https://youtu.be/_wnHDNgnNqs

I had two sets shorter lower control arms made, 16 7/8" and 17" which allowed me to get my the pinion to angle spot-on so that my U-Joints could be in phase with my driveline.

This did shorten the wheelbase of the car, which was something I planned to do anyway since everything was custom fit plus I really wanted the rear wheels to be centered in the arches.

Car Without Body On & Shock Move:
https://youtu.be/PCngiKoopkA

Car With 16 7/8" Lowers:
https://youtu.be/IGYtX-3p7xk

In addition, I had my lowers made at Spohn, but they do custom work an also offer adjustables for Factory Five Cars.

Customer Lower Contol Arms:
https://www.spohn.net/shop/Custom-Parts-Services/Custom-Built-Control-Arms-Panhard-Bars-and-Torque-Arms/Custom-Tubular-Control-Arm-Poly-Poly-Ends-Fixed-Length.html

Adjustable Lower Control Arms:
https://www.spohn.net/shop/Factory-Five-Racing-MK3-MK4-Roadster/Adjustable-Rear-Lower-Control-Arms-with-Del-Sphere-Pivot-Joints.html

Good Luck!

Steve

[xlr8or]

Has the banana bar been welded to the rear axle? If not it's easy enough to adjust in more space.

[Jeff Kleiner]

If the top of your banana bracket is that far rearward it tells me that the upper link is adjusted long which makes me suspect that you have the pinion pointed upward (i.e. front high). Once again when we speak of pinion angle we are referring to the pinion shaft relative to the transmission's output shaft. When determining pinion angle the driveshaft does not come into play---you can leave it on the workbench, and in fact if you follow my method method for measurment described below it will be easier if you do just that

Don't get caught up or confused on any thoughts of horizontal. Think of it this way; when looking at the car from the side if you were to project one line from the transmission output forward and another line from the pinion shaft forward with your pinion angle at zero they would be parallel. If you put any angle to the pinion the two lines are not parallel and would get farther apart as they go forward. If the pinion were to be angled UP (relative to the trans) it's line would be above the output line; if it were angled DOWN the pinion line would be below. Below is what we're after.

Clear as mud? Maybe a visual will help. Here is a quick drawing I made when this topic came up again on the other forum a week or so ago:

http://thefactoryfiveforum.com/attachment.php?attachmentid=78314&d=1514586767

Doesn't matter whether the rear end is above or below the output centerline; 2 degrees down in relation to the trans output is 2 degrees down either way. Need more? print this image and then rotate the paper so that the line through the engine is pointing up or down left to right...see how the line through the pinion still remains pointing 2 degrees downward in relation to the line through the engine?

My method for ease of measurement:
Set ride height then put the car on jackstands so that the axle is loaded. We don't care if the frame is dead nuts level; we're only going to look at the difference between output shaft & pinion. We know that the crankshaft and trans output shaft are parallel therefore the face of the damper/ crank pulley is perpendicular to the output. We also know that the pinion flange face is perpendicular to the pinion. See where I'm heading? For me it is easier to get a good measurement with the magnetic angle finder by reading vertically on the crank pulley/ damper and pinion flange rather than trying to work with the horizontal shafts themselves. Once you can see the two angles you can then calculate the difference. Generally with these cars we want the pinion down ~1-2 degrees the input is pointing down in relation to the transmission output shaft. Reason being is so that when the axle tries to rotate it's input upward under accelleration the pinion angle becomes less. This rotation is especially more pronounced on a 4 link car using the soft rubber bushings in OEM Mustang arms vs. a 4 link car with poly bushings or a 3 link with polys in the lowers and the solid upper link.

Hope all that helps!

Jeff

[GoDadGo]

This You Joint Phasing Video May Be Of Help Too:

https://youtu.be/Idk3BVDVHq4

My pinion points up because I'm Special, but standard build point down a from what I understand.

[BB767]

78322

It looks like the ABSOLUTELY NOT diagram if you flip it upside down.

[BB767]

karlos - I am pretty sure I understand what needs to be accomplished. The question is how?
Gromit - I agree, thus I need even MORE clearance than what I have indicated.
GoDad - Yes, I have seen adjustable lower control arms on the market, those do look like a possible option, however i am concerned about wheel location in the well when I am done. And I still may have clearance issues with the shocks and their mount (yes, I have already turned them over).
xir8or - Moser welds them, and there is also the issue of the shock brackets.
Jeff - I am confident I have the measurements correct to within 1 degree for the pinion and within .1 degree for the transmission. See my "depiction" picture post above for clarification.

[GoDadGo]

My car is 2 degrees positive and is my pinion angle set at ZERO to 1 degree for pre-load.

If the "Absolutely Not" picture has your engine on the left and the differential on the right,
then you need to pull the upper link in so that you i can get it in the "Moderate Strain" zone.

U-Joints need to be set up in this manner (Moderate Strain Zone) in order to cycle the needle bearings.

Also, from what I understand the Ford driveline is about a degree or two downward facing so the pinion also needs to be a degree or two downward facing.

Does This Help?

[NAZ]

If your set-up looks like the "Absolutely Not" picture then I think you found the source of your vibration. I also think you would find it easy to adjust out of this issue with adjustable upper and lower control arms. By adjusting both you can rotate the axle to change the pinion angle AND maintain the same wheelbase so that if your axle is centered in your fenders you can keep it in that same location.

[karlos]

The problem with setting the pinion angle without regard to the driveshaft angle is that it can lead to operating angles that will kill a u-joint in short order. Here's an extreme example.

http://thefactoryfiveforum.com/attachment.php?attachmentid=78315&d=1514590788


The red centerlines are parallel, and as a result the pinion angle is the ideal zero. But the u-joints would clearly be very unhappy under these conditions.

In one of my previous posts on this topic (is there a more confusing topic in all of roadster-land?) I mentioned that I got looking at the angle of my driveshaft (hope Miller doesn't see that one) a few weeks after my driveline setup had been completed. Driveshaft was at about 5 or 6 degrees and, when viewed outside the context of just the pinion angle, didn't look right. When I did the initial install I was laser-focused on pinion angle and didn't even realize I should be paying attention to anything else. After a little research it became apparent that complete driveline setup needs to consider more than just pinion angle. Although my pinion angle was within spec the operating angles were way in excess of 3-degrees and probably would have led to noise, vibration, and an early death sentence for the u-joints.

Recognizing that pinion angle is really nothing more than the difference between the two operating angles, it would seem to make more sense to dial-in the operating angles first and then simply verify that the difference between them is less than 1-degree. That way all the important parameters come together at the same time.

Just trying to save others from the same slow-learner syndrome I seem to be inflicted with. Not that much fun to invest an hour or two in setting up your driveline only to find out you did it wrong and have to start over.


With regard to the how: does your differential currently slope upward or downward (when moving from the front of the car to the back of the car)? And which way are you unable to move it? Can't move the pinion flange up or down?

[BB767]

GoDad - You might have missed the part where I said to turn the picture upside down, correction is the opposite direction.
NAZ - I think you have the best understanding of the problem and a good solution. Only problem is there is no more clearance between the shocks and their mount, I cannot extend the upper control arm any further (thus rotating the axle) without them rubbing on each other even if the lowers were shortened. (Yes, I have already inverted the shocks for more clearance.)
Carlos - I agree but I do not think that will be a problem for two reasons, one, the driveshaft is so short they would have to be off a lot more to make this a concern and two, any fix will bring the angles you depict closer together (better) than they are now. You are correct and that is exactly what I am looking at, the RELATIVE angle (difference) between the transmission output shaft and the pinion itself.

[BB767]

If using the convention that the slope of the drivetrain is measured going from front to rear, a component slopes downward if it is lower at the rear than the front. A component slopes upward when it is higher at the rear than it is in front. If both your transmission and your differential slope downward as described above, you should be looking at this:

http://thefactoryfiveforum.com/attachment.php?attachmentid=78312&d=1514582993


If this is the case, then your pinion angle is zero. Right where you want to be. However, the u-joint operating angles still need to be checked to confirm no more than 3-degrees at either end. You'll need to measure the driveshaft angle in order to check this. Use this handy online calculator once you have your measurements: http://spicerparts.com/calculators/driveline-operating-angle-calculator

Objective is to get the operating angles at each end to be 3-degrees or less, and the difference between them (the pinion angle) to be 1-degree or less.

This is what the online calculator returns if I plug in your numbers. Note that I had to guess on the driveshaft angle. When I was done messing with my car it measured 2.2-degrees, so I just used that as a placeholder. If these were your final numbers you'd be in pretty good shape. Pinion angle is zero, and the 3-degree max operating angle is only exceeded by 0.2-degrees. Don't forget to compensate for driveline squat that will occur under hard acceleration. You'll probably want some upward slope bias on the differential so that the pinion angle and the operating angles are within spec while under load.

Good luck!


http://thefactoryfiveforum.com/attachment.php?attachmentid=78313&d=1514583922

karlos - I read your post more thoroughly. The numbers I initially posted were estimates to illustrate the reverse angle I am concerned about. Using the top diagram you posted maybe you can plug in the actual numbers and see what you get. The engine is angled as depicted 4.5 degrees. For the rear end (pinion), rotate the depicted axle housing counter clockwise until the left end of the red line touches the imaginary ground. Make this angle 1.5 degrees. Now what does the calculator tell you?

[NAZ]

I'm sure there are plenty of ways to deal with shock clearance issues but photos of the clearance issue would help. Bottom line is you have to correct the problem that is causing the out of phase u-joint vibration. That means rotating the pinion angle or the angle of the trans output shaft. With all the builders that have accomplished this I have to think it's just a matter of determining what's different about your build that is making that difficult. If this was a wild modified build I'd suggest you look into a double-cardan u-joint but it's hard to believe that would be necessary.

[BB767]

78325

NAZ, I totally agree. I just don't understand why mine is so different (difficult) and was hoping someone else had run into the same problem and found a fix. The photo is an old one as I was concerned about this problem long ago. I discussed it with Dan at FFR and he said not to worry about it as they tend to look that way during the build.

[phileas_fogg]

My build includes the 1988 Thunderbird IRS, so I've got nothing to add but encouragement. Driveline angle, pinion angle, and U-joint phasing are all details you need to get right; good on you for sweating these details. I spent at least a week* dinking around with measurement methodology (so I could get repeatable measurements), various spacers ('cuz you have to torque everything to spec to make sure it's right), and jacking the car off the ground & putting it back down ('cuz you can't install spacers with the car only 4" off the ground). If you're stymied work on something else while your subconscious generates options in the background.

Keep at it & you'll get there!


John

* Yeah, I know; but while I'm not fast, I am slow. ;)

[NAZ]

OK, I've dealt with this one before and it's an easy fix. I used a hole saw to cut a relief in the bracket to add clearance for the shock. I don't recall the size but was just slightly smaller than the I.D. of the bracket where it joins the axle tube.

[Jeff Kleiner]

BB767,
One last question...is the rear axle loaded and at approximate ride height while you're taking measurements and making adjustments?

Jeff

[NAZ]

Guess I should have clarified what I did. Remove the shock from the bracket and measure down from the top edge of that bracket 3/16" to 1/4" and centered. Drill a 1/4" hole here for your hole saw pilot drill. Select a hole saw that's slightly smaller than the I.D. of the bracket (think of the bracket as a channel and measure the inside of the channel). Carefully drill with the hole saw to remove basically half a hole worth of material from the top edge of the shock mount bracket that's welded to the axle tube. Clean up the cut edges and touch-up paint.

Make sure to set the hole saw pilot drill so it does not drill into the axle tube.

When you reinstall the shock you will have more clearance -- should be enough to rotate the axle to adjust the pinion ange.

[Jeff Kleiner]

BB767,
One last question...is the rear axle loaded and springs set at approximate ride height while you're taking measurements and making adjustments? In the photo above it appeasr that the axle is hanging and the amount of threads on the adjuster show a high ride height.

Jeff

[karlos]

Now what does the calculator tell you?

Yeah, really bad...

http://thefactoryfiveforum.com/attachment.php?attachmentid=78327&d=1514599929

Max operating angle is 2X too high; pinion angle is 4.5X too high. Question: the engine's at 4.5-degrees downward slope with a 1-inch shim already in place? Doesn't seem right, as my engine measures 0.2-degrees upward slope (essentially level) with a shim thickness of about 7/8". Also, 7/8" raised the transmission so far that the midshifter contacted the 3/4" frame tubes in the transmission tunnel. You sure the motor mounts are seated and everything else is located properly?

A couple observations:

- With a front operating angle in the vicinity of 6 degrees, this probably explains the noise
- At 1.5 degrees nose down, the differential is probably about where it needs to be. It will likely rotate up to about 0 degrees while under power (note that I used 0 degrees in the calculator based on this assumption)
- Looks like you mainly need to get the engine closer to level. If you could reduce the 4.5 degree reading to about a 1.0 degree reading, all angles would be in spec

You didn't indicate what your driveshaft angle is. I'm still guessing 2.2 degrees. The actual value will change things somewhat, so please make the necessary updates. But something seems wonky with your engine/trans angle...

[BB767]

Thanks NAZ, more good options.
Jeff, in that photo I am not sure and the car was light. Now the car is more near finish and the axle is on jack stands (loaded) and the ride height is set, still looks the same as far as shock clearance as that does not change with load (well, maybe a 16th on an inch, but not a noticeable change).
Mr. Fogg, thanks for the encouragement.

[NAZ]

Wow, the engine / trans is angled at 4.5-degrees??? I missed that part earlier.

Typically you may see 2-deg +/- but I don't think I've ever come across one close to 4-deg. So I suggest you start there and determine what it will take to get that engine / trans combo closer to 2-deg or less if possible. Then work on pinion angle and use Jeff's 2-deg down setting to start with. And if you still have shock clearance issues the fix I suggested before should take care of that problem.

[BB767]

Wow, the engine / trans is angled at 4.5-degrees??? I missed that part earlier.

Typically you may see 2-deg +/- but I don't think I've ever come across one close to 4-deg. So I suggest you start there and determine what it will take to get that engine / trans combo closer to 2-deg or less if possible. Then work on pinion angle and use Jeff's 2-deg down setting to start with. And if you still have shock clearance issues the fix I suggested before should take care of that problem.

Just went out and and verified it, 4.5 at the output housing and at the crank pulley.

I can't see messing with the engine mounts. They are stock FFR mounts that fit the 351 block perfectly.

I have already raised the transmission about an inch (the limit of the existing bolts). I am hesitant to jack it up to much for fear of causing other unforeseen problems elsewhere. Any other suggestions for this?

[NAZ]

Well since you're running EFI there's probably nothing to keep you from running that steep angle and adjusting the pinion to match. However, I'll tell you if this was my car I'd have to have something very compelling to keep me from lowering the front of that engine.

[karlos]

Like you, I have a 351 block with a TKO 600 and the FFR-supplied motor mounts. The engine/trans should be roughly level with a shim thickness of only about 3/4". Something's not right if you're 4.5 degrees down with a 1" shim installed.

Is the pin on the motor mount in (not on top of) the chassis bracket hole as shown below?


http://thefactoryfiveforum.com/attachment.php?attachmentid=78328&d=1514607172

[BB767]

Yes. The mounts all dropped into the the slots and holes very nice and easy!

[BB767]

It is a Dart block if that makes any difference, it does look different than the one in your picture, at least in that small area.

[karlos]

The photo shows a Coyote, but does a good job of illustrating the pin/hole fitup. Couldn't find a clear shot of my specific motor mount, so the photo is borrowed. I've got a Ford block so not an exact match either. Maybe someone else with a Dart block could chime in with engine position vs. shim thickness?

[BB767]

78329783307833178329

[karlos]

Yes, see post #22 above. Need the driveshaft angle to get accurate numbers but I believe you will be able to get everything within spec if you can get the engine closer to level.

[BB767]

Much lower and my oil pan would be below the frame. The tail shaft of the trans was setting on the crossbar before I added shims. now it is about 1 inch above it. It appears there is plenty of clearance above the transmission to the frame, the frame now is about even with the shift lever bolts.

[BB767]

Yes, see post #22 above. Need the driveshaft angle to get accurate numbers but I believe you will be able to get everything within spec if you can get the engine closer to level.

It is 3.5 down towards the rear.

Even if I could get the engine level, which I doubt is possible, the pinion is still angled down (towards the front) about 1.5 degrees which is still in the NO area.

[NAZ]

I must have missed what the issue was with raising the rear but it sounds like you now have clearance to accomplish raising the trans, if so then that's your mission for today. To help you as you wrestle with this you can download a smart phone app from Tremec (Tremec Tool Box) that will allow you to use your smart phone to take angle measurements and automatically calculate if your drivetrain is "in spec". You can use the app to play "what if" until you get all the angles to play nice. For instance, when you take a reading and the app tells you you're out of spec you can play with the angle of individual components to see how close that gets you to your goal. A nudge here and a nudge there and soon you'll be happy and so will your drivetrain.

[BB767]

Thanks NAZ, that's what I have been using all along, at least the angle measurement part of it.

The issue with raising the trans is it just doesn't seem right to have it jacked way up off the mount (your talking about 3 inches or more). Seem's like a set up for future problems with movement and bolts working loose, what about the torque on those bolts and the mounts?

[phileas_fogg]

You said Dart block. Some folks have reported that there is a fin or protrusion on the block that prevents the motor mount from seating all the way. The solution is to grind the mount (not the block!) and eliminate the interference. Have you checked that?


John

[BB767]

You said Dart block. Some folks have reported that there is a fin or protrusion on the block that prevents the motor mount from seating all the way. The solution is to grind the mount (not the block!) and eliminate the interference. Have you checked that?


John

Yep, had to grind off only about a 32nd of an inch, very small correction and it fit nice and tight.

[GoDadGo]

BB767,

When I was fighting my pinion angle, I made some temporary lower control arms from 2" square tubing.
I drilled some holes at 17" (Stock is 17 5/8") to see if rotating the bottom forward would allow my banana bracket to clear and also to get the pinion angle right.
I also pulled the shocks so that I could use my floor jack to articulate the rear suspension.
Taking this action also required me to move the top of the shock further aft so that they would clear the lower mounts.
I don't know if making a set of test/temporary lower control arms would help you, but it did help me.

Steve

PS: I too have a Moser Rear (Dana 44 / TSD-500) but I think my brackets were welded in the correct location, but I'm not feeling the love on yours.

[BB767]

Thanks Steve, I'll certainly add this idea to the pile of options I am accumulating. I appreciate all the input from everyone as it gives me a well rounded view of the problem and possible solutions!

[edwardb]

Yep, had to grind off only about a 32nd of an inch, very small correction and it fit nice and tight.

Maybe there's some variation I'm not aware of (certainly very possible!) but that doesn't sound right. My DART block along with the Energy Suspension mounts took considerably more than that to get the mounts to sit flat on the block.

Something just isn't right here. You're doing a pretty typical installation. Doesn't make sense you should have to raise the TKO more than 3/4 - 1 inch. Something else is going on.

[karlos]

Yep, something's out of sorts. Assuming you can find it and then get the engine roughly level, all your angles will come in. Some new numbers based on the now known driveshaft angle.

http://thefactoryfiveforum.com/attachment.php?attachmentid=78338&d=1514653799


Three scenarios are shown. Left: current situation (angles unacceptable); middle: how the numbers would look with a level engine (angles marginal but acceptable); right: numbers with pinion rise under power accounted for (angles look great).

I think this shows pretty clearly it's the engine/trans angle that needs to be addressed. If you can get it close to zero degrees with a shim thickness in the neighborhood of 1" you'll be all set.

[BB767]

Yep, something's out of sorts. Assuming you can find it and then get the engine roughly level, all your angles will come in. Some new numbers based on the now known driveshaft angle.

http://thefactoryfiveforum.com/attachment.php?attachmentid=78338&d=1514653799


Three scenarios are shown. Left: current situation (angles unacceptable); middle: how the numbers would look with a level engine (angles marginal but acceptable); right: numbers with pinion rise under power accounted for (angles look great).

I think this shows pretty clearly it's the engine/trans angle that needs to be addressed. If you can get it close to zero degrees with a shim thickness in the neighborhood of 1" you'll be all set.

The issue with raising the trans is it just doesn't seem right to have it jacked way up off the mount (your talking about 3 inches or more). Seem's like a set up for future problems with movement and bolts working loose, what about the torque on those bolts and the mounts? As previously stated I have already shimmed it up one inch to where it is now at 4.5 degrees!

It seems to me if the "banana" bar and shock mounts were relocated only a slight amount on the axle everything would be good. All I need is 3 degrees up on the pinion and I think I would be within limits. (Trans down 4.5, pinion up 1.5 equals 3 degree difference in the acceptable direction)

[karlos]

The angle calculator is your friend. Link is provided in post #2. Use it to consider various hypotheticals so that you have an idea of what you're trying to achieve before you start modifying the car. If I understand correctly, I believe you're proposing changing the slope on the differential from its current 1.5 degrees upward to 1.5 degrees downward (a total change of 3 degrees). If you plug those numbers into the calculator you'll see that the pinion angle still ends up being a factor of 2 too high (assuming a driveshaft angle of 2 degrees and a differential angle of 1.5 degrees, pinion angle ends up being 2 degrees).

Just to be clear, no one is suggesting that you raise the back of the transmission 3 inches. If you need something like 3 inches in order to get the engine approximately level, then there's another issue at play here. Need to find what that is first and then move on to setting up the driveline.

[BB767]

Can some of you tell me what your pinion angle is? I am talking about the pinion shaft itself coming out of the rear axle housing. Is it pointed down or up in relation to the frame of the car?

Stepping back a moment; almost all vehicles have the engine/transmission mounted at some angle down towards the rear of the vehicle, although I will agree some may be exactly level, that's just the way it is. Therefor, most vehicles have the pinion shaft pointing slightly up, or again, some may be level, again, that is just what is most common. But none that I have ever seen have been mounted pointing down!

So, are all yours different? Do your pinions point down towards the ground in the front? Mine does and I do not think that is normal. But if you all have the same thing going on, then I guess I am wrong. I would just like to establish this fact before moving on to raising the transmission.

[karlos]

Look at Kleiner's post (#6). You want about 2 degrees nose down relative to the transmission output shaft. You're currently at 1.5 degrees nose down on the pinion. But your transmission is at 4.5 degrees the opposite direction. So the angles add. 1.5 + 4.5 = 6 degree operating angle. No good. But if your engine were roughly level, you'd be 1.5 degrees nose down relative to the trans output shaft. Perfect.

[karlos]

Is that dark semicircle in your photo a shadow or a gap?

http://thefactoryfiveforum.com/attachment.php?attachmentid=78339&d=1514661689

[edwardb]

Can some of you tell me what your pinion angle is? I am talking about the pinion shaft itself coming out of the rear axle housing. Is it pointed down or up in relation to the frame of the car?

Stepping back a moment; almost all vehicles have the engine/transmission mounted at some angle down towards the rear of the vehicle, although I will agree some may be exactly level, that's just the way it is. Therefor, most vehicles have the pinion shaft pointing slightly up, or again, some may be level, again, that is just what is most common. But none that I have ever seen have been mounted pointing down!

So, are all yours different? Do your pinions point down towards the ground in the front? Mine does and I do not think that is normal. But if you all have the same thing going on, then I guess I am wrong. I would just like to establish this fact before moving on to raising the transmission.

Each of my four builds (including the newest one on the lift right now) have the diff pointed up toward the front. With the engine/trans typically pointing down in the 1-2 degree range (that's what mine have been), that equals an acceptable pinion angle.

[Joee]

Look at Kleiner's post (#6). You want about 2 degrees nose down relative to the transmission output shaft. You're currently at 1.5 degrees nose down on the pinion. But your transmission is at 4.5 degrees the opposite direction. So the angles add. 1.5 + 4.5 = 6 degree operating angle. No good. But if your engine were roughly level, you'd be 1.5 degrees nose down relative to the trans output shaft. Perfect.

Right, BB767 you have to have an assembly problem your rear sounds fine. Most of us only need to fine tune the rear and done. This thread is way too much going on. Is there a builder /owner in your area to stop by and look at your car. Experienced eyes can usually spot a problem immediately.

[BB767]

Is that dark semicircle in your photo a shadow or a gap?

http://thefactoryfiveforum.com/attachment.php?attachmentid=78339&d=1514661689

Hi Karlos, I went out and inspected it closely, there is no gap, the mounts sit square and flush on the frame pad.

[BB767]

Each of my four builds (including the newest one on the lift right now) have the diff pointed up toward the front. With the engine/trans typically pointing down in the 1-2 degree range (that's what mine have been), that equals an acceptable pinion angle.

Thanks Edward. I feel if my pinion were pointed up, (as yours is) or even level, the problem would be easy to solve. I just do not understand why my pinion is pointed down with no adjustment left. My trans angle may be excessive compared to most but I view the main problem as the pinion angle, if that were more like yours there would not be a problem.

But on the other end;
Do you have any builds with the tunnel still open? I would like to know the clearance between the transmission and the frame. There is a silver cover plate on the top of my TKO600 just in front of the shift lever. I have 2 inches from it to the bottom of the frame cross member. Also, the gap between the transmission tail shaft and the frame cross member (underneath). Mine is currently 1 inch.

[BB767]

Right, BB767 you have to have an assembly problem your rear sounds fine. Most of us only need to fine tune the rear and done. This thread is way too much going on. Is there a builder /owner in your area to stop by and look at your car. Experienced eyes can usually spot a problem immediately.

Joee, can you tell me the angle of your pinion shaft? Is it currently pointed up or down in relation to the frame?

[Joee]

I have a stock 91 302 block, stock Ford motor mounts, T5 trans. My rear is down about 2 deg from trans out put shaft just like Jeff's picture. My transmission mount sits on A frame with a washer as a spacer.
http://i207.photobucket.com/albums/bb110/JoeE13/FFR%205294%203link/100_8518.jpg

[edwardb]

Do you have any builds with the tunnel still open? I would like to know the clearance between the transmission and the frame. There is a silver cover plate on the top of my TKO600 just in front of the shift lever. I have 2 inches from it to the bottom of the frame cross member. Also, the gap between the transmission tail shaft and the frame cross member (underneath). Mine is currently 1 inch.

The completed Roadster sitting in the garage right now (#8674) wouldn't be particularly easy to measure. It's a Coyote with TKO and IRS. So probably not applicable to yours. But dug through some pictures and found this picture of Mk4 Roadster #7750 with a DART 347 and TKO600. It's a 5-link solid axle. Still not the same as yours, but a little similar. Trans spacer is 3/4-inch.

http://i867.photobucket.com/albums/ab234/edwardb123/Factory%20Five%20Mark%204%20Roadster%20Build/Update%2001252014/IMG_2426_zps0fc55316.jpg (http://s867.photobucket.com/user/edwardb123/media/Factory%20Five%20Mark%204%20Roadster%20Build/Update%2001252014/IMG_2426_zps0fc55316.jpg.html)

[BB767]

The completed Roadster sitting in the garage right now (#8674) wouldn't be particularly easy to measure. It's a Coyote with TKO and IRS. So probably not applicable to yours. But dug through some pictures and found this picture of Mk4 Roadster #7750 with a DART 347 and TKO600. It's a 5-link solid axle. Still not the same as yours, but a little similar. Trans spacer is 3/4-inch.

http://i867.photobucket.com/albums/ab234/edwardb123/Factory%20Five%20Mark%204%20Roadster%20Build/Update%2001252014/IMG_2426_zps0fc55316.jpg (http://s867.photobucket.com/user/edwardb123/media/Factory%20Five%20Mark%204%20Roadster%20Build/Update%2001252014/IMG_2426_zps0fc55316.jpg.html)

Exactly what I am looking at. Can you estimate the distance between that crossbar and the silver cover plate below it?

[BB767]

I have a stock 91 302 block, stock Ford motor mounts, T5 trans. My rear is down about 2 deg from trans out put shaft just like Jeff's picture. My transmission mount sits on A frame with a washer as a spacer.
http://i207.photobucket.com/albums/bb110/JoeE13/FFR%205294%203link/100_8518.jpg

To help narrow down the problem, can you tell me what the angle of the rear end is in relation to the frame of the car? In the picture it appears level or slightly nose high.

[Joee]

I will tell you later not near car and that pic is 10 yrs old;)

[edwardb]

Exactly what I am looking at. Can you estimate the distance between that crossbar and the silver cover plate below it?

It's been a few years since that picture was taken :p and I don't own it any more. I would put it in the 1/2 - 3/4 inch range. The rubber shift boot, as I recall, was right at the bottom of the crossbar. Hope that helps.

[CraigS]

BB767 a couple of questions. Is your trans a-frame on top of the tab on the main frame or under it? I know it's not much difference, maybe 3/8 inch, but could be helpful raising the trans w/o using a thicker shim. Can you get some pics of your rear axle including the banana bracket? I wonder if there is a chance it is clocked incorrectly relative to the pinion. I think you alluded that it is the FFR supplied axle assembly w/ the bracket welded, but there could always be a mistake there.

[rich grsc]

What tranny mount are you using? Take a picture of your mount and the A-frame.

[BB767]

78345783467834778348

Couple of requests for photos.
390 shows A frame looking aft. It is mounted on top of the bracket with shims installed.

[BB767]

783497835078351

404 shows that air cleaner and injection body almost level with the frame

[BB767]

BB767 a couple of questions. Is your trans a-frame on top of the tab on the main frame or under it? I know it's not much difference, maybe 3/8 inch, but could be helpful raising the trans w/o using a thicker shim. Can you get some pics of your rear axle including the banana bracket? I wonder if there is a chance it is clocked incorrectly relative to the pinion. I think you alluded that it is the FFR supplied axle assembly w/ the bracket welded, but there could always be a mistake there.

My feeling exactly, is this clocked incorrectly? I'll try and get photos of that that are clear.

[BB767]

BB767 a couple of questions. Is your trans a-frame on top of the tab on the main frame or under it? I know it's not much difference, maybe 3/8 inch, but could be helpful raising the trans w/o using a thicker shim. Can you get some pics of your rear axle including the banana bracket? I wonder if there is a chance it is clocked incorrectly relative to the pinion. I think you alluded that it is the FFR supplied axle assembly w/ the bracket welded, but there could always be a mistake there.

Can you tell anything odd from the pictures?
78352783537835478355

[karlos]

Not sure how much difference it makes, but it doesn't appear the shim is in the correct location.

http://thefactoryfiveforum.com/attachment.php?attachmentid=78358&d=1514688276


Picture's kinda dark, but it looks like you've got a stack of 3 washers that add up to maybe 3/8" or so? That would explain the tail-down trans angle. Shim's not thick enough, plus at that location vs. under the trans mount the shim is less effective in producing an angle change. Suggest you try removing those washers, set the A-frame back down on the chassis tab, take the bolts out of the transmission mount, and then raise the back of the trans until you have a 3/4"-1" gap between the transmission and the transmission mount. Then recheck the engine/trans angle. Guessing you'll be much closer to zero degrees. If so, you can put in a new (thicker) shim under the trans, leave the differential where it is, and all driveline angles will be close to the desired values.

[BB767]

Not sure how much difference it makes, but it doesn't appear the shim is in the correct location.

http://thefactoryfiveforum.com/attachment.php?attachmentid=78358&d=1514688276


Picture's kinda dark, but it looks like you've got a stack of 3 washers that add up to maybe 3/8" or so? That would explain the tail-down trans angle. Shim's not thick enough, plus at that location vs. under the trans mount the shim is less effective in producing an angle change. Suggest you try removing those washers, set the A-frame back down on the chassis tab, take the bolts out of the transmission mount, and then raise the back of the trans until you have a 3/4"-1" gap between the transmission and the transmission mount. Then recheck the engine/trans angle. Guessing you'll be much closer to zero degrees. If so, you can put in a new (thicker) shim under the trans, leave the differential where it is, and all driveline angles will be close to the desired values.

OK, I'll take a look at that tomorrow.

[johnnybgoode]

Here's how I adjusted mine if it's of any help. Very similar to Jeff's diagram in post#6. I made up a couple of 3/4" spacers out of some 1" AL thick wall round tubing stock on the lath. Jacked up the transmission and bolted them up under the transmission mount with longer 2" grade 8 bolts and lock washers. I reset the pinion angle to 1.8*. The crank pulley measures 87.5* (or 2.5* downward angle) and the pinion flange is 89.3* (or 0.7* upward angle) which gives me the 2* differential that is required (your pinion flange should be close to 90*). If you have a digital level with a relative angle setting you can zero the level to the crank pulley and the reading you get on the pinion flange will be the number you want, mine's 1.8*. As I remember the 3/4" spacer got me about 1.5 to 2* less downward angle on the motor/trans. Before the spacer it measured 86*. Hope this helps. Good Luck. Scott

[BB767]

78432

OK, I went out this morning and raised the transmission until it almost touches the frame above it. It requires a shim thickness of 1 and 7/8 inches. It is now pointing down 1.5 degrees just like most of yours. Take a look at my depiction of the current angles and see what you think I should do now.78433

[NAZ]

Can't comment on the spacial position of the engine and trans but using Jeff's negative 2-degree static setting, rotate the pinion up until the angle is ~2-deg less than the output shaft. That would make the pinion shaft pointing down at 0.5-deg if your trans output shaft is pointing down 1.5-deg. Then check your driveshaft angle. The pinion angle has to be measured at ride height.

If the rear end won't rotate because of shock clearance then use the method I detailed earlier to get clearance.

When you are taking the engine / trans angle is the chassis level with the world, at ride height, or ???

[karlos]

Is the driveshaft really at 22.7 degrees? That's about 10 times what I would expect to see (mine ended up right at 2 degrees). Something's really, really wrong. Starting to wonder about the accuracy of your angle measurements. Did you say you're using an app on your phone? Do you have another way to try to confirm the numbers? Something like this, maybe (only $5 at Harbor Freight): https://www.harborfreight.com/dial-gauge-angle-finder-34214.html

[BB767]

Can't comment on the spacial position of the engine and trans but using Jeff's negative 2-degree static setting, rotate the pinion up until the angle is ~2-deg less than the output shaft. That would make the pinion shaft pointing down at 0.5-deg if your trans output shaft is pointing down 1.5-deg. Then check your driveshaft angle. The pinion angle has to be measured at ride height.

If the rear end won't rotate because of shock clearance then use the method I detailed earlier to get clearance.

When you are taking the engine / trans angle is the chassis level with the world, at ride height, or ???

I am using the Tremec app on my phone for the measurements. Since I assume that is level with the world (as are the other measurements) I am simply looking at the differences to check limits.

Karlos, I'll go out and double check now.

[Jeff Kleiner]

http://thefactoryfiveforum.com/attachment.php?attachmentid=78433&d=1514743365

This = 6 degrees; way too much.

http://thefactoryfiveforum.com/attachment.php?attachmentid=78432&d=1514742506

This = 3 degrees; still too much but closer.

The only way to change the relationship is by lowering the front of the engine, raising the rear or lengthening the upper link. I too have been suspicious about your method of measurement and ask once again, what is your ride height in the rear? Show us a photo of the top of the banana bracket and panhard bar brace interface. Doesn't matter in the least whether the chassis is level with the world...for pinion angle we're only interested in two things; the angle of the output shaft and angle of the pinion shaft. I've been building these cars for years using a hardware store angle finder like Karl showed and never had a problem. It's like Jacob the Amish IT guy says "Sometimes the old ways are the best ways" (youtube it :)).

Jeff

[BB767]

7843478435


With transmission raised.

[BB767]

784367843778438

Best I could get photos of rear axle.

Ride height is 4 3/4 front and rear, give or take 1/4.

I have a couple of angle gauges but most are to big to get into the area. The walls of my house measure "0" on the Tremec measurement app, I don't know what else to say. When remeasuring the driveshaft I come up with 21.9 this time. The measurements may not be 100% precise but they appear to always be within 1 degree. Close enough to get this problem figured out, I can get a more precise measuring device when I am closer to the target numbers and correct positions..

[BB767]

78439784407844178442

More photos showing my clearance issues with the shock mounts and the banana bar. I think your idea of trimming the shock mounts will work but what can I do about the banana bar?

[Jeff Kleiner]

Maybe the camera is playing tricks but when I view your 78435 photo it sure looks like the top of the axle tube is very near even with the top of the 4" chassis tube:

If that's indeed the case the only way I can see this being possible is if the axle is hanging. PLEASE give us some wider shots showing how it sits during your measurements.

Jeff

[Erik W. Treves]

Maybe the camera is playing tricks but when I view your 78435 photo it sure looks like the top of the axle tube is very near even with the top of the 4" chassis tube:

If that's indeed the case the only way I can see this being possible is if the axle is hanging. PLEASE give us some wider shots showing how it sits during your measurements.

Jeff

yeah that looks like full droop to me as well Jeff. Although in one of the pics you can see the jack stands...

the rear shock looks like it's angled pretty good.. don't remember mine be like that.... can you take some pick of the lower control arms and mounting of the brackets... I would expect needing over 1" of tranny spacer.. for sure you need some... the few I have done, I think I am in the 3/4" range

[BB767]

http://thefactoryfiveforum.com/attachment.php?attachmentid=78433&d=1514743365

This = 6 degrees; way too much.

http://thefactoryfiveforum.com/attachment.php?attachmentid=78432&d=1514742506

This = 3 degrees; still too much but closer.

The only way to change the relationship is by lowering the front of the engine, raising the rear or lengthening the upper link. I too have been suspicious about your method of measurement and ask once again, what is your ride height in the rear? Show us a photo of the top of the banana bracket and panhard bar brace interface. Doesn't matter in the least whether the chassis is level with the world...for pinion angle we're only interested in two things; the angle of the output shaft and angle of the pinion shaft. I've been building these cars for years using a hardware store angle finder like Karl showed and never had a problem. It's like Jacob the Amish IT guy says "Sometimes the old ways are the best ways" (youtube it :)).

Jeff

I understand and agree. The front of the engine is not going down without some kind of special motor mounts or major modifications to the frame supports, probably not possible. The rear cannot come up any more as it is almost touching the frame above it now. The only option left is somehow raising the rear pinion angle. This is the basic premise of the whole post and still is. How in the world am I going to get that done? That is the question.

As far as the measurements go, the Tremec app measures level to the earth, period. I assume everyone here understands that. As you said, it makes no difference what the numbers are, what matters is their relationship to each other. Parallel within 1 degree, total difference not to exceed 3 degrees. It's that simple, but again, I cannot figure out how to get there with the restrictions I have on the pinion angle adjustment!

[Jeff Kleiner]

Gotta' head out to the shop and get some work done...I'll check back in later to see if there are any updates.

Jeff

[BB767]

784437844478445

I know someone said the shock adjustments looked high but as they are, with 4 3/4 ride height, the side pipes only clear the neighborhood speed bumps by one and a half inches. Any lower and I will not be able to leave my driveway!

[Erik W. Treves]

thanks for the pics..that looks ok to me of first look.

[BB767]

yeah that looks like full droop to me as well Jeff. Although in one of the pics you can see the jack stands...

the rear shock looks like it's angled pretty good.. don't remember mine be like that.... can you take some pick of the lower control arms and mounting of the brackets... I would expect needing over 1" of tranny spacer.. for sure you need some... the few I have done, I think I am in the 3/4" range

From the top of the axle tube to the top of the 4 inch main chassis tube is exactly 4 inches.

The rear axle is supported by jack stands, the front main tubes are supported by jack stands near the tow hoops. In this configuration there should be slightly more weight on the rear axle than when on the (front) wheels. But the car is not finished so this should closely approximate the finished ride height (in theory).

[Joee]

I went out and rechecked my car as it is up on stands now. My frame is level front pulleys are off so my crank is 3 deg up my trans out put 3 deg down, my rear is 5 deg down. Net 2 deg.
My rear ride height in 4". Here is a pic of my magnetic gauge and a shot of my shock in relation to mounting bracket.
http://i207.photobucket.com/albums/bb110/JoeE13/FFR%205294%203link/IMG_2685_zpsmnn0roau.jpg
http://i207.photobucket.com/albums/bb110/JoeE13/FFR%205294%203link/100_4453.jpg

[Joee]

784437844478445

I know someone said the shock adjustments looked high but as they are, with 4 3/4 ride height, the side pipes only clear the neighborhood speed bumps by one and a half inches. Any lower and I will not be able to leave my driveway!

My pipe clearance (UTC) is about 2 3/4 - 3" there is a fine art to speed bumps. Unless yours are huge...

[BB767]

I went out and rechecked my car as it is up on stands now. My frame is level front pulleys are off so my crank is 3 deg up my trans out put 3 deg down, my rear is 5 deg down. Net 2 deg.
My rear ride height in 4". Here is a pic of my magnetic gauge and a shot of my shock in relation to mounting bracket.
http://i207.photobucket.com/albums/bb110/JoeE13/FFR%205294%203link/IMG_2685_zpsmnn0roau.jpg
http://i207.photobucket.com/albums/bb110/JoeE13/FFR%205294%203link/100_4453.jpg

EXACTLY! Everything looks and sounds very similar to mine EXCEPT the the rear! Yours is down 5 deg (I assume you are measuring front to rear) and mine is UP 1.5 degrees with no way to adjust it further!

[Joee]

How is your banana bracket attached? If aligned properyly with the sleeve turned all the way in the rear should be pointing down almost 10 deg, then by lengthening it the rear comes up.
http://i207.photobucket.com/albums/bb110/JoeE13/FFR%205294%203link/100_8516.jpg

http://i207.photobucket.com/albums/bb110/JoeE13/FFR%205294%203link/100_8518.jpg

[BB767]

How is your banana bracket attached? If aligned properyly with the sleeve turned all the way in the rear should be pointing down almost 10 deg, then by lengthening it the rear comes up.
http://i207.photobucket.com/albums/bb110/JoeE13/FFR%205294%203link/100_8516.jpg

http://i207.photobucket.com/albums/bb110/JoeE13/FFR%205294%203link/100_8518.jpg

Now you are confusing me. When you say "the rear comes up" Do you mean the pinion comes up or the rear cover plate comes up?

When I extend the upper control arm, the pinion comes up. Sorry, I have not gotten the technical terms completely straight yet, I am trying.

[Joee]

Now you are confusing me. When you say "the rear comes up" Do you mean the pinion comes up or the rear cover plate comes up?

The plate that the drive shaft bolts too goes from pointing down, toward ground, with adjuster turned all the way in and as adjuster is turned, to lengthen it, the plate starts to rise from facing down to level to facing up towards car's under carriage.

When I extend the upper control arm, the pinion comes up. Yes thats right

I am not good with tech terms either, thats why I try not to use them :)

[BB767]

In order to help me determine if my axle is set up correctly could someone please do the following measurement(s) for me? To be relevant it must be a Moser 8.8 with the welded brackets.

I made the axle perfectly level as measured on the back housing cover mounting surface. Then using a level I measure from the FRONT of the axle tube to the furthest rear point on the top of the banana bracket. That distance measures 10 and 7/16 inches on my axle.

I then measured the angle of the shock mounting brackets, the welded on part.

From above they have a "U" shape. When measuring the vertical angle on the tips of the "U" my phone leveling app shows between 0 and 4 degrees (tops angling towards the front of the car) depending on which of the 4 points I measure. I know this is a rather imprecise measurement but it still might help if yours come out to be something more than 5 or less than 0.

Anyway, thanks for helping me narrow down my problem.

[BB767]

I am not good with tech terms either, thats why I try not to use them :)

LOL, good, we are on even terms.

You have confirmed my suspicion. I have the Moser rear end which is welded. That plate on mine cannot be adjusted up (in our terms) more than (negative) -1.5 degrees! The banana bar hits the frame and the shocks hit the mounts.

[GoDadGo]

BB767,

Just sent you a private message.

Steve

[NAZ]

Might be interesting to look at your axle position relative to a chassis datum and compare to others'. So a measurement from the front side of the axle tube to some point on the chassis for a sanity check. If your axle is further to the rear than other builds that may shed some light on the banana bracket interference issue. And in the meantime it wouldn't hurt to make sure your axle is square in the chassis as if it is skewed that may also cause an interference issue.

[BB767]

Might be interesting to look at your axle position relative to a chassis datum and compare to others'. So a measurement from the front side of the axle tube to some point on the chassis for a sanity check. If your axle is further to the rear than other builds that may shed some light on the banana bracket interference issue. And in the meantime it wouldn't hurt to make sure your axle is square in the chassis as if it is skewed that may also cause an interference issue.

NAZ - Right side is 8 and 9/16, left side is 8 and 11/16. Measurements are from the REAR of the axle tube to the end of the 4 inch tube. (Easier to get an accurate measurement from the back of the axle.)

[NAZ]

Small error but nothing that would cause an interference issue. Now let's see if someone with a car like yours can provide a dimension from the same points.

Adjustable LCAs will allow you to adjust pinion angle without causing the banana bracket to hit but it will shorten your wheelbase a bit. Not sure if that would create another problem or not. Maybe one of the guys who has a car like yours has an opinion.

[BB767]

Small error but nothing that would cause an interference issue. Now let's see if someone with a car like yours can provide a dimension from the same points.

Adjustable LCAs will allow you to adjust pinion angle without causing the banana bracket to hit but it will shorten your wheelbase a bit. Not sure if that would create another problem or not. Maybe one of the guys who has a car like yours has an opinion.

That appears to be what this is boiling down to. Adjustable lower control arms and doing something with the shock clearance. Steve (GoDadGo) had the same problem and used shorter lowers with good results. Only question now is, am I on my own on this or will FFR and Moser help me out?

[Joee]

That appears to be what this is boiling down to. Adjustable lower control arms and doing something with the shock clearance. Steve (GoDadGo) had the same problem and used shorter lowers with good results. Only question now is, am I on my own on this or will FFR and Moser help me out?

To me you are spending too much time and re-engineering of the rear end. Are you absolutely married to your Moser? Mine is a '99 Ford 8.8 with our cars weight not a problem with your power plant you are just going to smoke tires anyway.

T.he kit is set up to use stock Mustang parts of given years. I bet your whole problem is because you aren't using the Ford pumpkin you arent using the small black square link that goes from pumpkin snout to banana bracket. My bad I am not familiar with the Moser option.
http://i207.photobucket.com/albums/bb110/JoeE13/FFR%205294%203link/100_8522.jpg

[edwardb]

Don't want to pile on, but with all the talk about pinion angle, just needs to be said that 22+ degree U-joint working angle (if it's accurate) is completely unacceptable. Spicer and others typically talk about anything beyond 3 degrees will affect bearing life and likely will be felt. Some offset is desirable, but you're way beyond that. Given the position of the diff (pointing down vs. up) and the shock interference issue, seems that something is wrong with the rear suspension. Fixing it with spacers under the transmission beyond the usual 3/4 to 1 inch maybe isn't getting to the root cause. But then an argument could be made for just the opposite too. Hang in there. This will get resolved.

One thing I have to ask though. You say you have ride height at 4-3/4 inches. Which is OK to start. But you're doing it with jack stands under the suspension and no wheels/tires. I assume you adjusted the coilovers to achieve the 4-3/4 inches. Are you sure your wheel hubs (and resulting suspension overall) are the same height they would be with the wheels/tires mounted? I don't think it would make a huge difference and won't solve anything. But it would be possible to have wrong settings on the coilovers if the relative position of the suspension isn't the same as it would be if the wheels/tires were mounted and sitting on the ground.

Since the Moser option is offered by FF (and I assume where you purchased it) I would start by calling FF. Maybe you have already.

[karlos]

I can see Steve needing to do something unique as his setup is anything but standard. But your setup is fairly common and should follow the same trends as other similar builds. I haven't yet seen that anything wrong has been identified with the rear end, other than not having enough adjustment capability to overcome an unusual situation with the engine/trans position.

Still think the fact that you're 1.5 degrees tailshaft down with a nearly 2" thick spacer is an indication of some as-yet unidentified problem up front. Very much out of family with respect to what others have reported. Even if you can make everything come in by moving the rear, it seems to me that it's ultimately a band-aid for something else going on up front.

Not trying to be critical. Hope it doesn't sound that way. Just not sure all the issues contributing to this problem have been identified.

[GoDadGo]

That appears to be what this is boiling down to. Adjustable lower control arms and doing something with the shock clearance. Steve (GoDadGo) had the same problem and used shorter lowers with good results. Only question now is, am I on my own on this or will FFR and Moser help me out?

I purchased my Rear End directly from Moser & we all know that my set up is far from typical.
In your case, I'd contact Factory Five since you purchased the unit through them.
For the record, I think they welded the brackets a few degrees off.

[BB767]

Edward - The ride height and measurement were originally set weeks ago with the car on the ground, measurement from the frame to the ground on a level surface.

I spent all afternoon fabricating and installing permanent shims. The final tail shaft (and crank pulley) angle is 2.4 degrees with shims equaling just over 1 inch.

I was able to tweak the rear end slightly and get it to near 0 degrees (plus or minus .5 due to difficulty getting an accurate reading). That leaves the drive line at 10 degrees. Again, all of these measurements are relative to the ground so we are just looking at relative positions. 78450

[karlos]

Guys...

Let's assume the brackets on the rear end are incorrectly located. And that after you get a replacement with the brackets in the correct position you are able to then set the differential with the pinion flange pointed up at at 3.5 degrees. Note that 3.5 degrees is required to get the pinion angle to be 1 degree with the transmission pointed down at 4.5 degrees. The operating angles in this scenario are 7.5 (front) and 6.5 (rear)*. Not even remotely acceptable. And as the pinion climbs under power the rear angle gets even worse (8.5).

One way or the other I believe the situation with the trans angle needs to be addressed.


* Assumes a 3 degree driveshaft angle. May be worse than that as connecting a 4.5 degree low tailshaft with a 3.5 degree high pinion will require a pretty steep angle. If worse than 3 degrees (likely, I think) the operating angles also become worse.

[BB767]

I can see Steve needing to do something unique as his setup is anything but standard. But your setup is fairly common and should follow the same trends as other similar builds. I haven't yet seen that anything wrong has been identified with the rear end, other than not having enough adjustment capability to overcome an unusual situation with the engine/trans position.

Still think the fact that you're 1.5 degrees tailshaft down with a nearly 2" thick spacer is an indication of some as-yet unidentified problem up front. Very much out of family with respect to what others have reported. Even if you can make everything come in by moving the rear, it seems to me that it's ultimately a band-aid for something else going on up front.

Not trying to be critical. Hope it doesn't sound that way. Just not sure all the issues contributing to this problem have been identified.

karlos - What do you propose? Not trying to be smart, I really hope you can find a problem, but.......

The block is what it is, nothing to change.

The motor mounts are what they are. I have shaved them enough so the engine sits right in them like they were made for it. I put them on while the engine was hanging on the hoist, I could view theme easily 360 degrees, the fit was sweet! Bolts went in by finger until they needed the torque wrench.

The mounts sit on the frame very nicely as well. When the engine was initially set on the mounts, the pins did not go into the holes, I know what you are talking about when you ask about them. A small push with a pry bar and they fell right in snugly. They are sitting in there tight. Absolutely nothing to change unless they need to be modified from stock.

That's it for the front of the engine! What could I change?

The rear is now permanently jacked up as most of you suggested with a final angle of 2.4 degrees. From what some have said here I think that is now within the "normal" range. Although I feel I have constructed some pretty substantial shims, I would not raise it any higher. Also, I do not remember being asked what the current angle of the frame is, but I just checked that as well. It is down 1.4 degrees so the angle of the engine/transmission relative to the frame is only 1 degree down, which is even better!

But none of this completely fixes the problem, so, what to do now?

[BB767]

Guys...

Let's assume the brackets on the rear end are incorrectly located. And that after you get a replacement with the brackets in the correct position you are able to then set the differential with the pinion flange pointed up at at 3.5 degrees. Note that 3.5 degrees is required to get the pinion angle to be 1 degree with the transmission pointed down at 4.5 degrees. The operating angles in this scenario are 7.5 (front) and 6.5 (rear)*. Not even remotely acceptable. And as the pinion climbs under power the rear angle gets even worse (8.5).

One way or the other I believe the situation with the trans angle needs to be addressed.


* Assumes a 3 degree driveshaft angle. May be worse than that as connecting a 4.5 degree low tailshaft with a 3.5 degree high pinion will require a pretty steep angle. If worse than 3 degrees (likely, I think) the operating angles also become worse.

Using the calculator you originally posted 4.5, 3, 3.5 equals a perfect setup. Working angles of 1.5 and .5.
Even if the drive shaft raised a degree due to resetting the rear it still would have worked, 4.5, 2, 3.5 = 2.5 and 1.5.

Now, using 1.4, I cannot make it work. I think I should have left it alone and fixed the rear end.

[NAZ]

This thread is so long I sometimes loose my place of where you are right now. But it seems you still need to rotate the pinion angle up a bit. You're too close to give up on rotating the pinion angle now. Remember, with a short driveshaft the angle changes significantly as you change elevation of the front or rear u-joint. Rotating the axle up to change the pinion angle will also elevate the rear u-joint and change the operating angle. You may get this closer than at first it appears possible.

[karlos]

Difference in the numbers is due to the assumed slope of the driveshaft. I assumed upward; you selected downward. Based on your photos it appears your pinion flange sits (a lot) lower than the trans output shaft. Is that typical for a solid axle car? On my IRS car the pinion sits above the trans, which explains why I selected upward.

Very frustrating, I'm sure, and I sympathize. Trying to help but we're all hamstrung by only being able to work off of what we can see in the photos. I appreciate that you've looked for and not found any obvious issues with the motor mounts. Something is in fact different, however, as a 3/4" shim in my car (same chassis, same engine, same trans) has the output shaft angle above zero (above level).

Is there anybody local with knowledge of these cars that can come take a look?

[karlos]

Searched the forum to try to find photos of a typical installation. Came across this one from Paul's 7750 build. Can you confirm you're seeing something similar (pronounced downward slope on the driveshaft)? I believe Paul's photo shows the situation with the rear suspension unloaded (looks like the car is on a lift). But if I understand correctly, you're seeing a similar driveshaft angle with the suspension loaded, right?

If so, I now understand why you initially had so little shim under the transmission. Gotta get the tailshaft down to more closely match the height of the pinion flange and therefore reduce the severity of the driveshaft angle.

So if I'm understanding correctly, not sure I'm seeing a fix. If you lower the transmission you improve the driveshaft angle but make the pinion angle worse. If you raise the transmission you improve the pinion angle but make the driveshaft angle more severe. Same thing happens as you raise and lower the pinion flange (improve one to the detriment of the other).

All seems to be driven by the fact that the pinion flange is very low as compared to the output shaft. Is that unique to the Moser? How did you other guys running a Moser get it to work?


http://thefactoryfiveforum.com/attachment.php?attachmentid=78457&d=1514822861

[NAZ]

Here's some food for thought. I ran the trig calculations for the longer driveshaft and for every inch of height change between the u-joints you will see ~5-deg change in angle. Of course the shorter one will be even more. So again, I'd suggest you rotate that rear end and move the pinion angle up to achieve Jeff's 2-degree offset and then measure the operating angle again. I think you're close enough that a nudge here and a nudge there and you will find the sweet spot.

From my experience building off-road vehicles with extreme operating angles; the u-joint angles are much more important than the driveshaft operating angle. Think about that 5-deg change per inch and consider how much angle change you get in these cars with the operating range of the rear end suspension travel.

[GoDadGo]

This Thread Is Now Bugging The C--p Out Of Me So Sorry Gang But This Chevy Guy Has The Solution!

17" Lower Arms will do the trick as long as you move the Upper Shock Mounts back a bit.

Look at this video (39-51 seconds in) to see how I, Your Humble Chevy Guy From The Swampy South, corrected the problem.

https://youtu.be/PCngiKoopkA

Good Luck, God's Speed & May God Bless You All For Putting Up With Me!

Steve

NOTE: I've got the Moser TSD-500 rear with welded banana bracket and I'm 99% sure that my brackets were not placed in the proper location.

[Jeff Kleiner]

I just went to the garage, pulled back the cover and shoved the camera under mine (please forgive the grime; the poor old car hasn't gotten much love the last couple of years). This is typical of a 3 link driveline regardless of transmission---remember, the engine sits in the same place in the chassis and the crankshaft & trans output are in line therefore the trans output centerline winds up in the same location whether T5, TKO or whatever. They all make the same straight line front to back.

http://thefactoryfiveforum.com/attachment.php?attachmentid=78471&d=1514830537

A few years ago we had a builder who encountered issues with the rear axle location when he put the body on. Pinion angle was brought up early on and the builder assured us that it was measured and set properly. His presented some of the same areas of concern as yours; interference at the panhard brace to banana bracket as well as with the coilovers to axle brackets. It just so happened that he had a Moser rear and there were questions about the possibility of the mounts having been improperly located. Lots of pictures, conversations, suggestions and measurements later it was finally determined that he had not correctly measured and set the pinion angle after all and this was the cause of all of his problems.

http://www.ffcars.com/forums/17-factory-five-roadsters/288073-need-advice-rear-tire-rub.html

No offense or disrespect intended but with all you have going on I just can't help wondering if what we're dealing with isn't a hardware problem but rather an error in either your method of measurement or interperatation of the data.

I'll keep following along and good luck.

Jeff


78471

[BB767]

Thanks again all. Lots to think about. Now that I have a pretty good idea of what my options are I am going to hold up here a while until I hear back from FFR.

I am kind of pissed off at myself, I think I cross threaded one of the transmission mount bolts when I reinstalled it. By any chance do any of you have one you are not using? (A new transmission mount I mean.)

[GoDadGo]

I'll dig through my "Didn't Use Box" to see what stuff I have that fits the standard Ford set up; however, I may have discarded the driveline mounts.
I don't know if I have them, but if I do I'll be happy send the trans mount to you.

[BB767]

I'll dig through my "Didn't Use Box" to see what stuff I have that fits the standard Ford set up; however, I may have discarded the driveline mounts.
I don't know if I have them, but if I do I'll be happy send the trans mount to you.

Thanks Steve, if you do, let me know shipping and what they are worth to you and I'll send it along.

[karlos]

FWIW, I am also reluctant to attribute what’s going on to a hardware problem. I say that because there are a number of measurements that are far outside the realm of what’s typical for similar builds.

- 2” thick shim needed to get to some semblance of normal engine/trans angle
- with trans and differential as close to level as you can get them, driveshaft is at almost a 30 degree angle

Since you’ve checked your installation and not found anything unusual, that might point to the measurements or the interpretation of the measurements as the actual problem.

Again, not trying to be critical. Sincerely hoping you get it straightened out.

- Karl

[BB767]

FWIW, I am also reluctant to attribute what’s going on to a hardware problem. I say that because there are a number of measurements that are far outside the realm of what’s typical for similar builds.

- 2” thick shim needed to get to some semblance of normal engine/trans angle
- with trans and differential as close to level as you can get them, driveshaft is at almost a 30 degree angle

Since you’ve checked your installation and not found anything unusual, that might point to the measurements or the interpretation of the measurements as the actual problem.

Again, not trying to be critical. Sincerely hoping you get it straightened out.

- Karl

karlos - I hesitate to answer due to the risk of offending someone, ALL input I am receiving here is appreciated whether I agree with it or not.

Having given the disclaimer, I do not understand why some of you just cannot believe that there is a problem with the rear axle and the it MUST be with my measurements!

I am telling you, this does not pass the common sense eyeball test! When I look at the angles I do not have to measure them with anything to tell you there is a zig zag in the drive line! It is also plainly obvious just looking at it without any math that the angle from the output shaft is not that bad, it doesn't matter if the transmission angle is 4.5, 10 20, or upside down, the angle relative to the drive line is excellent! (4.5 to 3.5 originally) So, looking at the angle between the pinion gear shaft and the drive shaft, again it is obviously apparent that this angle is the problem, it needs to be straighter! It is also obvious that tilting the rear axle higher in the front by only 3 or 4 degrees will make that angle almost parallel WITHOUT making the other angle worse, in fact it would be improved to less than one degree. This observation is confirmed using the calculator you posted above. No amount of measuring, correct or incorrect, will change the fact that this angle is messed up! Yes, I am stuck on my preconceived notion. I asked for advice here HOPING that you would find an error that I had made. So far I have checked and tried every thing you have suggested. Since none of that has worked I have no choice but to conclude that my initial observations were correct. I guess what annoys me is not the fact that you persistently question my measurements, it's the fact that unless you come to the same conclusion I have, I still could be wrong! So, now that I have vented, please keep the suggestions coming if you have any new ones. in the mean time I expect a call from FFR sometime today to get their take on the issue. Thanks again for you input everyone.

[Joee]

Steve

NOTE: I've got the Moser TSD-500 rear with welded banana bracket and I'm 99% sure that my brackets were not placed in the proper location.

This prob bugs me too. If this is the case then I guess you do need to reconfigure hardware.

[jwebb]

Confused??
From manual:
"To set the pinion angle, make sure that your ride height is where you want it, and then adjust the upper arm until the desired angle is reached. We usually run about 2° up on the rear axle, but you can adjust this to fit your particular set-up."

Everything above is saying 2 degrees DOWN not UP??

[BB767]

Confused??
From manual:
"To set the pinion angle, make sure that your ride height is where you want it, and then adjust the upper arm until the desired angle is reached. We usually run about 2° up on the rear axle, but you can adjust this to fit your particular set-up."

Everything above is saying 2 degrees DOWN not UP??

Yea, I can never keep straight what each post is trying to say. From what I understand the correct way to state the pinion angle is looking towards the rear of the car, in this case, I need about 2 to 3 degrees DOWN. I tend to simply say that the pinion shaft itself, which comes out of the front of the pumpkin, needs to go up. I think that is what the manual is saying, but again, not positive. Regardless, it is clear mine needs to go up (in the front) to be within 1 degree of the input shaft and within 3 degrees working angle. Any change in the other angles (transmission or drive shaft) just makes the numbers worse and impossible to reconcile.

[Joee]

Confused??
From manual:
"To set the pinion angle, make sure that your ride height is where you want it, and then adjust the upper arm until the desired angle is reached. We usually run about 2° up on the rear axle, but you can adjust this to fit your particular set-up."

Everything above is saying 2 degrees DOWN not UP??

This graphic, thanks Jeff, explains it all visually. The idea is that when the car is under hard acceleration the rear will twist so it lifts about a degree or so and then parallel with the trans out put shaft. ** Also the manuals are a guide which is fine tuned by builders like Jeff :) **
http://thefactoryfiveforum.com/attachment.php?attachmentid=78314&d=1514586767

[Big Blocker]

QUOTE: We usually run about 2° up on the rear axle, but you can adjust this to fit your particular set-up."

Everything above is saying 2 degrees DOWN not UP??

What needs to happen here is an unsolicited user pole about the picture Jeff submitted . . . How many think the pinion is "down" in his picture and how many think it's "UP"??

Once you all agree on which is which, this issue will be resolved for good (I hope).

I'l post my answer after some responses by the reading, and arguing population.

Doc

[BB767]

http://spicerparts.com/videos/measuring-driveline-operating-angles

This video from Spicer answers the question. I admit I have been stating the rear end angle incorrectly most of the time but have tried to be clear about what I was referring to. Unfortunately it in no way changes my predicament, the angles are STILL wrong. From now on I will use the correct terminology. Amazing what you learn here!

Currently setting at 2 degrees DOWN, 4.5 degrees DOWN and 2 degrees UP.

http://spicerparts.com/calculators/driveline-operating-angle-calculator

Using this calculator, if I change the rear end angle to 1.5 degrees DOWN, I would have a decent set up. This is assuming that the driveshaft rises .5 degrees to 4 down (due to raising the end near the pinion). So I would end up with 2 down, 4 down, and 1.5 down leaving working angles of 2 on the front and 2.5 on the rear, which would decrease to 2 down under acceleration. All within the 1 degree parallel limit and 3 degree working angle limits!

[Vspeeds]

Interesting thread. I have the same Moser welded banana bar. The rear end is mounted and I see it leaves little room for adjustment against the panhard frame when the arm is extended. It’ll be awhile before i mount the engine and tranny but ill keep this thread in mind.

[Jeff Kleiner]

What needs to happen here is an unsolicited user pole about the picture Jeff submitted . . . How many think the pinion is "down" in his picture and how many think it's "UP"??



If my drawing didn't provide a clear picture of pinion pointing down relative to the output I verbalized it repeatedly in post #6:


If the top of your banana bracket is that far rearward it tells me that the upper link is adjusted long which makes me suspect that you have the pinion pointed upward (i.e. front high). Once again when we speak of pinion angle we are referring to the pinion shaft relative to the transmission's output shaft. When determining pinion angle the driveshaft does not come into play---you can leave it on the workbench, and in fact if you follow my method method for measurment described below it will be easier if you do just that

Don't get caught up or confused on any thoughts of horizontal. Think of it this way; when looking at the car from the side if you were to project one line from the transmission output forward and another line from the pinion shaft forward with your pinion angle at zero they would be parallel. If you put any angle to the pinion the two lines are not parallel and would get farther apart as they go forward. If the pinion were to be angled UP (relative to the trans) it's line would be above the output line; if it were angled DOWN the pinion line would be below. Below is what we're after.

Clear as mud? Maybe a visual will help. Here is a quick drawing I made when this topic came up again on the other forum a week or so ago:

http://thefactoryfiveforum.com/attachment.php?attachmentid=78314&d=1514586767

Doesn't matter whether the rear end is above or below the output centerline; 2 degrees down in relation to the trans output is 2 degrees down either way. Need more? print this image and then rotate the paper so that the line through the engine is pointing up or down left to right...see how the line through the pinion still remains pointing 2 degrees downward in relation to the line through the engine?

My method for ease of measurement:
Set ride height then put the car on jackstands so that the axle is loaded. We don't care if the frame is dead nuts level; we're only going to look at the difference between output shaft & pinion. We know that the crankshaft and trans output shaft are parallel therefore the face of the damper/ crank pulley is perpendicular to the output. We also know that the pinion flange face is perpendicular to the pinion. See where I'm heading? For me it is easier to get a good measurement with the magnetic angle finder by reading vertically on the crank pulley/ damper and pinion flange rather than trying to work with the horizontal shafts themselves. Once you can see the two angles you can then calculate the difference. Generally with these cars we want the pinion down ~1-2 degrees the input is pointing down in relation to the transmission output shaft. Reason being is so that when the axle tries to rotate it's input upward under accelleration the pinion angle becomes less. This rotation is especially more pronounced on a 4 link car using the soft rubber bushings in OEM Mustang arms vs. a 4 link car with poly bushings or a 3 link with polys in the lowers and the solid upper link.

Hope all that helps!

Jeff

So there's my response to the poll Doc ;)

Jeff

[Papa]

I've been following this thread as I'm going to need to do some angle setting soon myself. Right now without any adjustments for ride height, my engine angles down (front to rear) 2.4 degrees. My rear end angles down back to front at 1.9 degrees. If I try to adjust the rear (3-link welded bracket from Moser) to get the rear angled parallel to the engine's angle, the banana bracket makes contact with the cross-brace that runs from the upper passenger side frame to the lower driver's side frame, and doing so would create what appears to be a ridiculous angle on the stubby drive line. I gather that I should account for about a 1 degree rotation up on the rear end under acceleration. I'll be watching.

[GoDadGo]

I'll dig through my "Didn't Use Box" to see what stuff I have that fits the standard Ford set up; however, I may have discarded the driveline mounts.
I don't know if I have them, but if I do I'll be happy send the trans mount to you.

Sorry, just finished digging through my "Cave Of Wonders" and I can't find the transmission mount.

[rich grsc]

It seems to me all the issues are with the Moser supplied rear ends. Looking at the pictures, it sure looks like the bracket is welded on incorrectly. I never had an issue getting the alignment correct on my 3 link.

[Big Blocker]

Jeff,

I never would question what your response would have been . . . we think alike and post alike on soooo many things.

FWIW, I almost didn't get involved with this thread due to the last one that went on-n-on forever.

But, that being said, I'm a softy for helping out other owners/builders.

Doc

[GoDadGo]

Amen Rich & Doc, Amen!

[BB767]

Papa and Vspeeds. Thank you for the posts! Maybe I am not the only one! Maybe you guys can help determine if I have totally screwed up or there really is a problem with the axles. Please keep me (us) updated here what you find as you set up your drive trains!

[DaveS53]

If you can't read this power train setup article and get the job done, you probably shouldn't be trying to build a car. It's not that complicated.

https://www.ccsdesigns.com/_builder/2/live/ie_driveline_service/uploads/files/Power%20Train%20Setup.pdf

[BB767]

If you can't read this power train setup article and get the job done, you probably shouldn't be trying to build a car. It's not that complicated.

https://www.ccsdesigns.com/_builder/2/live/ie_driveline_service/uploads/files/Power%20Train%20Setup.pdf

Good article, confirms what I have believed all along. Unfortunately if the structure does not allow for adequate adjustment to achieve these parameters what do you expect me to do, redesign and rebuild it myself? I do not have that expertise which is why I purchased a kit rather than try and engineer it from scratch!

[edwardb]

If you can't read this power train setup article and get the job done, you probably shouldn't be trying to build a car. It's not that complicated.

https://www.ccsdesigns.com/_builder/2/live/ie_driveline_service/uploads/files/Power%20Train%20Setup.pdf

If you haven't actually built a Factory Five kit, and in fact have been openly critical of every offering and holding up your own personal build as a shining example, probably best not to dispense build advice. Especially when it's condescending and borderline insulting. It's not that complicated.

[BB767]

If you haven't actually built a Factory Five kit, and in fact have been openly critical of every offering and holding up your own personal build as a shining example, probably best not to dispense build advice. Especially when it's condescending and borderline insulting. It's not that complicated.

Thank you Edward. I was really biting my tongue with my reply. You know I was already noticing that throughout this thread (and many others) your advice has been the most thoughtful, helpful, and professional. I (and I am sure MANY others) really appreciate it and would like to say a personal and public thank you.

[edwardb]

Thank you Edward. I was really biting my tongue with my reply.

I was too... And you're welcome. Really hope you can get this sorted out. Hang in there.

[broku518]

I am following this. I have a 3 link setup (Moser), just by looking at this it seems aright. But I will need to do some angle measurements to see for sure.
Thanks for posting the links and docs here.

I am not well versed in parts technical terminology, but can clearly follow pics and schemes. So thanks for posting those.

@BB767 - I am kinda glad you are dealing with this now, so it can help others. Feel your pain, hang in there!

Thanks,
Martin

[NAZ]

BB767, by now you'd probably prefer to shoot a NDB approach at night in a 50-kt crosswind but hang in there I'm confident you will get through this and have quite a story to tell family and friends. Seems your getting lots of help -- maybe more than you can process. Also seems you're not the lone ranger struggling with this and I'm sure others will benefit from your journey. Good luck and try to have fun along the way.

[boat737]

BB767, by now you'd probably prefer to shoot a NDB approach at night in a 50-kt crosswind but hang in there I'm confident you will get through this and have quite a story to tell family and friends. Seems your getting lots of help -- maybe more than you can process. Also seems you're not the lone ranger struggling with this and I'm sure others will benefit from your journey. Good luck and try to have fun along the way.

NDB I can handle... It's the GLS and Microwave apps that give me the helmet fire. (I'm old school, and old...)

BB, we all feel your frustration. I venture to say we've all been there with one problem or another on the builds. Keep at it, it's solvable.

If I may offer my 2 cents... After going through this (long) thread, I get the feeling that something is being missed, Don't know what though. I know you've looked at the setup 100 different times, from 50 different angles, but your setup is really no different than most of ours. I suggest back up and start fresh. Go from front to back, top to bottom. There's got to be a bracket backwards, or a mount upsidedown, or something not seated right, or wrong set of attachment holes... I have a 427w Dart, TKO600, Moser custom (Ford 9 inch), Energy Suspension mounts, a 7/8 inch trans spacer, and I'm within a degree everywhere.

[BB767]

Hey, thanks for all the encouragement, all of you! I am just stepping back for a few days to let the whole process settle down a bit. I have been through Dave and Dan at Factory Five and the case has been submitted to Jim in engineering (at FFR). I am trying to take another long slow look at the car to try and see ANYTHING else I could have done or missed. As the guy said above, it's really not that complicated (after researching 12 hours a day for the last couple of days and really learning the theory). As all of you know, there will be an outcome sooner or later, and we will all learn from it. Even with all this mess I still love the build and the car!

One request if I may. Anyone with the same axle they have received and installed since July or so and still have access to it, could you please try and measure what the angle is in relation to the frame when adjusted as far down as physically possible? I know the final setting is not dependent on this measurement, but the frame is the limiting factor in the range of angles available. Please be sure and use the correct terminology, a down or up angle is in reference to the rear cover plate, not the pinion gear itself. When my frame is level, the furthest down I can adjust my axle to is up, a positive 2 degrees. It will not go down any more due to bracket interference. I am using the Tremec Tool Box APP on my phone for the measurements. It is not perfect but seems to be precise to within about 1/2 degree. http://www.tremec.com/menu/tremec-toolbox-app/

[BB767]

NDB I can handle... It's the GLS and Microwave apps that give me the helmet fire. (I'm old school, and old...)

BB, we all feel your frustration. I venture to say we've all been there with one problem or another on the builds. Keep at it, it's solvable.

If I may offer my 2 cents... After going through this (long) thread, I get the feeling that something is being missed, Don't know what though. I know you've looked at the setup 100 different times, from 50 different angles, but your setup is really no different than most of ours. I suggest back up and start fresh. Go from front to back, top to bottom. There's got to be a bracket backwards, or a mount upsidedown, or something not seated right, or wrong set of attachment holes... I have a 427w Dart, TKO600, Moser custom (Ford 9 inch), Energy Suspension mounts, a 7/8 inch trans spacer, and I'm within a degree everywhere.

See my above post, that is what I am currently working on.
But even when I change something else up front as suggest above and tried by me, it only makes the angles worse! The only available variable in the equation that improves any of the angles is the rear axle. I certainly wish any of you were closer and could put a fresh pair of eyes on the thing.
There are only three points of contact forward, the motor mounts, perfectly set in their place, and the transmission mount, which I have totally disassembled and reinstalled three times during this post with only negative result. Again, the only adjustment left is the axle! FFR has already confirmed that I have it installed correctly. There just is not enough clearance.

By the way, what is all that stone age stuff, NDB, GLS, MLS? We only have GPS, INS, and some old ILS's on the 777.

[BB767]

NDB I can handle... It's the GLS and Microwave apps that give me the helmet fire. (I'm old school, and old...)

BB, we all feel your frustration. I venture to say we've all been there with one problem or another on the builds. Keep at it, it's solvable.

If I may offer my 2 cents... After going through this (long) thread, I get the feeling that something is being missed, Don't know what though. I know you've looked at the setup 100 different times, from 50 different angles, but your setup is really no different than most of ours. I suggest back up and start fresh. Go from front to back, top to bottom. There's got to be a bracket backwards, or a mount upsidedown, or something not seated right, or wrong set of attachment holes... I have a 427w Dart, TKO600, Moser custom (Ford 9 inch), Energy Suspension mounts, a 7/8 inch trans spacer, and I'm within a degree everywhere.

P.S. It would really help if I knew the angle of your rear axle. Everyone keeps saying that they are within a degree or two but no one ever tells me what those angles are! If I knew that I could spot the one mine does not match. How much do you want to bet it is the axle?

[johnnybgoode]

Your banana/shock brackets may in fact be slightly out of spec but I'd go with a set of these https://www.americanmuscle.com/bmr-double-adj-lca-spherical-0514.html or the ones Mark sells (I've used both, Mark's are very nice) and call it done. These are a great upgrade and you will probably only have to change your rear axle position by a 1/4" to bring the pinion into spec. The other advantage of a set of rod end LCA's is they will allow you to dial in your thrust angle at alignment time and will ride much better than the poly LCA's that tend to bind. If you wanted to check the theory you may be able to press the steel liners out of your current LCA's and put them back on and you should be able to move the axle back and forth a 1/4" and see what that does to your pinion angle. Even easier make yourself a set of mock ups out of 2x4 stock 1/4-1/2" shorter and bolt them up? Hope you figure it out. Good Luck. Scott

[boat737]

By the way, what is all that stone age stuff, NDB, GLS, MLS? We only have GPS, INS, and some old ILS's on the 777.

Did 16 years on the Triple myself. Probably best bird Boeing ever built. On Sparky now (the firebird, old lightning, nightmareliner) and it's doing it's best to kick my @$$. Keeps trying to out think me, I keep trying to not let it. Never trust electrons.

Now back to your regularly scheduled thread...

[BB767]

Well, it looks like this is going to end with a fizzle rather than a bang.

Dan says to ignore it, it works for everyone else so it will work for me. (Not an exact quote but my interpretation.)

They had me do more measurements on the axle, some were very similar to the axle they have there, some were not. They had me adjust the panhard bar and the upper control arm back and forth. They had me remove and reinstall the driveshaft. They (said they) reviewed all the photos I posted here and sent them and say that I have everything mounted, adjusted, and installed correctly.

I am finished at 2 degrees down, 4,5 degrees down, and .5 degrees up, more or less, all measurements are within 1/2 degree which is about as accurate as I can get with the Tremec APP.

Dan says if it has more problems in the future related to the angles they will "take care of it". I am a little leery, some of these angles are way out of limits according to every expert who has an opinion on the subject, but I am going to get on with the build on the assumption FFR knows what they are doing. Not much else to do.

Thanks again to ALL who posted. I'll update here if anything related comes up, otherwise, see you in the other posts.

[BB767]

Your banana/shock brackets may in fact be slightly out of spec but I'd go with a set of these https://www.americanmuscle.com/bmr-double-adj-lca-spherical-0514.html or the ones Mark sells (I've used both, Mark's are very nice) and call it done. These are a great upgrade and you will probably only have to change your rear axle position by a 1/4" to bring the pinion into spec. The other advantage of a set of rod end LCA's is they will allow you to dial in your thrust angle at alignment time and will ride much better than the poly LCA's that tend to bind. If you wanted to check the theory you may be able to press the steel liners out of your current LCA's and put them back on and you should be able to move the axle back and forth a 1/4" and see what that does to your pinion angle. Even easier make yourself a set of mock ups out of 2x4 stock 1/4-1/2" shorter and bolt them up? Hope you figure it out. Good Luck. Scott

Yea, Spohn makes some nice ones as well. If I get to paranoid about these angles that is my next step. In the mean time I am just going to go with FFRs recommendation.