The Alignment Thread

[Hindsight]

Seeing some more discussion of alignment lately. Thought I would create a thread to centralize alignment discussion. It would be great to see what people are running, how they are using the car, and what adjustments they have made to correct issues.

Base information that should be included:

Car Purpose (IE: Street only, mostly street and some autoX, mostly street and some road racing, autoX only, road racing only, etc)
Front Toe
Rear Toe
Front Camber
Rear Camber
Front Caster
Any modifications you had to in order to achieve your end result
Other comments, observations, changes that made an improvement


I will start:
- 80% street driving with 20% HPDE track days. No AutoX
- 3/16" total front toe in
- 1/4" total rear toe in
- Negative 0.85 degree front camber (couldn't get any more)
- Negative 0.75 degree rear camber
- ~3 degrees caster (couldn't get any more)

The car is a little "nervous" on the street and does veer a bit over some bumps. It isn't bad or anywhere near bad enough to be dangerous but ultimately I would like to sort it out if possible. Haven't had a chance to go around any corners yet. I believe I need to cut down the threads and tube nuts for my upper A-arms to get more caster and camber in the front if I need it. I got the above specifications from a post Wayne made some time ago (though he did specify a full 1 degree of negative camber in front which I couldn't obtain).

[FFRSpec72]

- 99% track, road racing. No AutoX
- 2mm total front toe in
- 2mm total rear toe in
- Negative 1.8 degree front camber (wanting more)
- Negative 2.5 degree rear camber
- 6 degrees positive caster (used 10mm spacers between LCA and LCA frame mount - hurricane bushing)

[Frank818]

Tony, why more camber at the rear?

[Mitch Wright]

100% track use baseline settings (30 miles on track as a go kart as shake down)
-2* front camber (so far that is all I can get from the right side, 2.25 can be had on the left. I did shorten up the studs on the upper control arms to allow for more ajustment.
+6* caster
1/8 total toe in
Rear
-2.5 camber
3/16 toe in
3.5" ride height front
3.75" ride height rear
Did spend a fair amount of time to minimize bumpsteer.
I did lip the stud on the lower control arm to gain some caster and camber adjustment. I have also made up some 1/8" spacers that can be added for additional front camber and caster.

[RM1SepEx]

Primary street use, possible autocross

Front 1/16 toe in total, -1 camber both sides caster 4 degrees both sides

rear 1/8 total toe in, -1 camber both sides

verrry finicky to get all the measurements exact and equal for both sides, took several hrs. w/o a friend with access to an alignment machine

ride height 4 1/2 all corners

it's a bit nervous (stole the term, fits the feeling well ;-) upon application of power, I need to get used to it

[Hindsight]

Good stuff, thanks folks.

Anyone here have any suggestions for alignment tools they want to share?

When I did mine, I did the string method for toe and to ensure the car was square. My garage floor was made in the 70's and isn't very flat, or smooth, so I used a cheap hardware store laser level that projects a cross line beam, and used the horizontal line to stack some cement pavers and tiles until I had a completely horizontal/level surface for all four tires. I lowered the car down onto them. I used a digital angle gauge to check caster and camber. Tape measure on the string to check toe. When turning the wheels right and left 40 degrees for the caster check, I made a "grease sandwich" of two pieces of plexiglass with grease between them and put them under the front tires. I used a protractor to check for 40 degrees of turn. In the future, I'd kind of like to have some turn plates but the cheapest ones that seem "ok" quality are still a couple hundred bucks and I doubt I will check or adjust caster very often so I may stick with the grease method for now.

Another question: Where are you measuring toe from? Front of the rim of the wheel? Somewhere on the sidewall? Somewhere near the front of the tire by the tread? I spent a long time researching that and there appears to be no consensus anywhere that I could find, so I measured mine towards the front of the tire.

[FFRSpec72]

Tony, why more camber at the rear?

because I can and can't in front, so I need more in front, for now until I fix that I will have more in rear

[FFRSpec72]

Good stuff, thanks folks.

Anyone here have any suggestions for alignment tools they want to share?

When I did mine, I did the string method for toe and to ensure the car was square. My garage floor was made in the 70's and isn't very flat, or smooth, so I used a cheap hardware store laser level that projects a cross line beam, and used the horizontal line to stack some cement pavers and tiles until I had a completely horizontal/level surface for all four tires. I lowered the car down onto them. I used a digital angle gauge to check caster and camber. Tape measure on the string to check toe. When turning the wheels right and left 40 degrees for the caster check, I made a "grease sandwich" of two pieces of plexiglass with grease between them and put them under the front tires. I used a protractor to check for 40 degrees of turn. In the future, I'd kind of like to have some turn plates but the cheapest ones that seem "ok" quality are still a couple hundred bucks and I doubt I will check or adjust caster very often so I may stick with the grease method for now.

Another question: Where are you measuring toe from? Front of the rim of the wheel? Somewhere on the sidewall? Somewhere near the front of the tire by the tread? I spent a long time researching that and there appears to be no consensus anywhere that I could find, so I measured mine towards the front of the tire.

So I used a jig that the center dive folks use, and it is centered on my frame at the front and rear, has a line down each side where I measure toe in/out (I pick a spot on the front and rear of the rim so it is the same on each side and look for the difference for toe in or out). then I use Longacre caster/camber gauge and a set of turn plates, and scales to do the corner weights

[tmoretta]

Just did my first track day with my 818S. Overall, I am pleased with the handling. However, the car is exhibiting more understeer than I want. Camber and Caster are pretty aggressive (Front - Camber - 2 Degrees neg., Caster 4 degrees pos. Rear - Camber 1.6 Degrees neg.) I am thinking of disconnecting the front sway bar (Subie 17 mm.) to make the turn in more neutral. Anybody with experience on this mod.

[Hindsight]

Sway bars effectively transfer more of the vehicle load to the end of the car the bar is on. So a front bar puts more load on the front tires which can cause them to overload before the rear. So yes, removing the front bar would help understeer. Adding a rear swaybar would help too, as would getting stiffer rear springs. Removing the front bar would be a great start though.

[tmoretta]

My car currently has the FFR 350 lb. springs in front and 400 lb. springs rear. Anyone know of a rear sway bar fitment for the 818?

[RetroRacing]

Front- ride height=3.5"
Camber= 3 degrees
Caster= 4.5 degrees
Toe= 1/16th in

rear- ride height=3.75"
Camber= 2.5 degrees
Toe= 1/16th in

[FFRSpec72]

Front- ride height=3.5"
Camber= 3 degrees
Caster= 4.5 degrees
Toe= 1/16th in

rear- ride height=3.75"
Camber= 2.5 degrees
Toe= 1/16th in

Nice, you must have done something to get the -3 camber ? Also what spring rates you using ?

[lclevert]

This request is directed to all who are posting their alignment specs here, not to anyone in specific.

It would also be good to know if you made any special modifications or used different parts in order to achieve the alignment specs that you have.

Now that we see what you got, we'd like to know how you got it.

Thanks

Skip

[Hindsight]

Not much needs to be done in the rear.

For the front, the most common mods are:
1. Increase caster by flipping the bracket on the rear of the lower control arm (hurricane bushing), or adding an aluminum spacers between the bracket and the lower control arm. I have seen people run spacers of 1cm. On mine, I just flipped the lower bracket. I was able to get to about 3 degrees of caster before running out of upper control arm adjustment.
2. Cut the nuts and threaded studs on the upper control arms to allow you to move them in for more caster and camber.
3. Bump steer (either spacing the tie rod end away from the spindle or moving the rack - the former being more common).

[RetroRacing]

Whiteline Front Control arm ANTI LIFT CASTER KIT RACE Impreza WRX STI 01-07 (put the left on the right, right on the left, shim until the arm moves freely up and down (we made solid alum ones but they are in the kit)
Cut the top nuts and threads on the upper control arm.
Made a bump steer kit out of 5/8" heim joints and a bump steer kit for a pinto. (see pic) Had to drill and tap our own alum connector, but easy peezy
55837

[brian b 36]

tom were did you do your track day

[tmoretta]

SCCA Track Night in America - Thompson, Ct.

[Canadian818]

I was just reading through Chad Plaven's thread again (there's a lot of good R&D in there!). He notes how dialed in his suspension was, lots of camber and toe out in the front. All the setups listed here, and everywhere else I recall seeing them have been toe in for both front and rear. Chad's car was posting some really good times, so are we missing something? Would the toe out only suit a track car on slicks?

[SixStar]

Just AX for now

Front camber - -3.5
Front Caster - 6.9
Front Toe - 0.02

Rear Camber - -2.5
Rear Toe - 0.03

[FFRSpec72]

I was just reading through Chad Plaven's thread again (there's a lot of good R&D in there!). He notes how dialed in his suspension was, lots of camber and toe out in the front. All the setups listed here, and everywhere else I recall seeing them have been toe in for both front and rear. Chad's car was posting some really good times, so are we missing something? Would the toe out only suit a track car on slicks?

A few of us have tried toe out, not the norm, we have gone to some really high caster and toe in, car seems pretty stable and responsive

[Mitch Wright]

My starting baseline is: (818R track only)
-2.7* Front Camber
+6* Caster
.062 total toe in
3.5 Front ride height
Rear
-2.5 Camber
.187 total toe in rear
3.75 rear ride height
Car will be on track next week.

[Hindsight]

How are you guys getting 6+ degrees of caster?

[FFRSpec72]

How are you guys getting 6+ degrees of caster?

I added a spacer

[Mitch Wright]

I just flipped the stud and slotted the top hole for additional camber which allowed me to adjust camber out and add caster.

[Hindsight]

Ahhh, both good strategies thank you. Tony, how thick of a spacer did you add? 1cm?

[FFRSpec72]

Ahhh, both good strategies thank you. Tony, how thick of a spacer did you add? 1cm?

10 mm spacer between the LCA and frame (where the 2 bolts go through, same place you flip the mount), the other which Mitch may have done is to slot the upper hole in the spindle adapter bracket as this will allow you to move in/out from the upper ball joint

[Hindsight]

Thanks Tony - I want to be sure I understand though. I thought the spacer was supposed to go between the control arm and the hurricane bracket, not between the bracket and the frame. The latter would move the rear of the control arm UP, while the former would move the rear of the control arm toward the outside of the car.

[FFRSpec72]

Thanks Tony - I want to be sure I understand though. I thought the spacer was supposed to go between the control arm and the hurricane bracket, not between the bracket and the frame. The latter would move the rear of the control arm UP, while the former would move the rear of the control arm toward the outside of the car.

Yes my mistake you are right, getting old here and can't remember much these days, so this did push the wheel forward as a side effect

[Hindsight]

Haha, I hear you about getting old. Thanks for the clarification. I am confident now that I'll be able to get to 6 degrees of caster.

[Mitch Wright]

Correct Tony, I flipped the stud, shortened the UCA studs and slotted the top hole one the FFR spindle mount for camber. installed the spindle with the camber maxed out. Then adjusted the camber to the desired setting using the front adjuster on the UCA which add caster.

[tmoretta]

I am thinking that everyone is referring to the aluminum lower control arm right? The steel one cannot be shimmed? Also, anybody have a picture of the slotted UCA. I am having trouble imagining what can be done to it.

[SixStar]

How are you guys getting 6+ degrees of caster?

Cut up the UCAs as well as using the wagon hole in front and the sedan holes in back.

[Hindsight]

Also, anybody have a picture of the slotted UCA. I am having trouble imagining what can be done to it.

The slot is referencing the spindle and spindle bracket, not the upper control arm.

For the upper control arm, you cut the rear tube nut down in length, as well as the studs that go into it so you can shorten it more to get both camber and caster.

The spindle slot is referring to the FFR spindle bracket that attached to the top of the WRX spindle. You can use the OE eccentric bolt in there (apparently if you drill out one or both sides of the bracket) which allows you to dial in some camber at the spindle+bracket without having to do it from the upper control arm, because adding camber via the upper control arm has the side effect of reducing caster - and we want as much caster as possible.

I'm going to post a video of the spindle eccentric bolt usage sometime this weekend if I have time to mess with it. I can only see it working properly if one side of the spindle bracket has a hole that is small enough to only let the threaded portion of the eccentric bolt through. Any larger and you would still be able to adjust camber there, but you'd have nothing but the pinch force of the bolt holding your camber in place.

[CU9DZ]

If anyone is still reading this discussion i have a question on getting more caster. Someone mentioned adding a shim to the rear end of the lower control arm i think to move it out somewhat. Does this affect the lower ball joint by moving it forward?67341
I tried to attach a picture but dont thing it worked.
Dave

[CU9DZ]

The alum lower control arm is in lower left of pic. The black piece bolts to it and pivots in the bushing. is this where a shim can be put?
Dave

[Hindsight]

Hi Dave,

The black piece the bolts to the lower control arm is where you can put the shim (between the black piece and the control arm). Yes this moves the lower ball joint (and hub and spindle) forward.

Having said all that, you don't really need to use the shim. You can flip that black piece over 180 degrees and bolt it back onto the control arm and that will give you some extra caster. If you do that, make sure you rotate the hurricane bracket (what that BIG rear bushing is surrounded by) 180 degrees as well or it will be upside down. Between doing this, and using the upper a-arm adjustments, you can get to around 5 degrees of caster and as much camber as you want. Getting more than -1 camber may require you to slot the upper spindle bolt hole in the spindle bracket though.

[CU9DZ]

Thanks. After I built the car and got it registered I got an alignment. Camber was at -.7 and caster 3.2
When I come out of a turn I have to pull the steering wheel back to center.
Since then I realized I had the steering rack in incorrectly. I had the C shaped piece on passenger side wrong so that side was higher than drivers side. Fixed that. Also had Front upper A arm pivot piece in with grease fitting up. Fixed that.
Now I have to get 5 or more caster and fix the bump steer issues.
Dave

[CU9DZ]

Another question. My lower control arm hurricane bracket is bolted to the frame using the inner set of holes. I have a WRX donor. If I move that bracket to the outer wagon holes does that move it too far out? How far does moving to outer holes move it? How far does flipping hurricane bracket move it?
Dave

[Hindsight]

I had the same steering wheel centering issue with 3 degrees caster as well. It's really dangerous because if you end up in an oversteer situation, you get no feedback from the steering wheel to help you correct and counter-correct. Between getting ~5 degrees caster, and fixing/adjusting the front and rear bump-steer, it totally transformed the car.

[Harley818]

Hi Hindsight,
I just completed my alignment, with the same goals as you post starting out. (although now I am wondering if I should have done 5 degrees of caster).
I wrote up a thread on the "Alignment process for the 818S" under the suspension threads. Could you take a look and see if I missed anything. Hoping to generate a process with one place for all the info.

Second question. I used 15.75 in for lateral link length. Mine measured 16 1/8 (but off a wagon). I am using the aluminum LCA's up front, and wanted to use sedan settings as I have adjustable lateral links in back. Do you know what the right length for sedans is ?
Thanks, your alignment info really helped me. Thanks for posting.

[CU9DZ]

I have not dealt with the bump steer problem yet. Just got the generic version of adjustable tie rod ends and rod to lower the connection point in mail. So it looks like there are multiple movements of the back of the lower control arm that can be done.
1. move the S shaped hurricane bracket to outside holes on frame.
2. just unbolt the bracket and put the flat side down, curved side up moving the bracket 180 degrees.
3. unbolt the black piece that attaches to aluminum control arm and spin that 180 degrees.
Some of these options might move the center line of rear bushing too far out/in and cause something to bind up.
Did anybody measure what each option did?
Dave

[Hindsight]

Harley, your write-up looked pretty good. The only thing I will say is that after buying and using a bump-steer gauge to check my bump steer, I found that even with the rear links parallel, I still had some bump out. You want zero bump, or some bump IN, but never out. Theoretically, if the rear links are exactly parallel, you are probably very close, but to play it safe, I would actually adjust them so the rear link is lower than the front link.... not much.... a tiny amount. This guarantees you'll have some bump-in which is safer than bump out. If you have a bump-steer gauge, use that instead.

I'm not sure about your caster method. Theoretically it could work but when I tried that method, I got a different number vs the method that an alignment shop would use so I went with the method where you check camber with the wheel out 15 degrees, zero out the digital gauge, then turn the wheel back to 0 then 15 degrees the other way and check camber again. The number you see is the true camber. It's a pain to do if you don't have turn plates but with some cardboard, tape, protractor, and sharpie, you can make it happen. I've done it twice now.

I also noted some slight differences from left front to right front. I attributed it to drift in the frame caused during welding by FFR.

Your string alignment procedure looked good. Very important that the strings are exactly the same width front to rear. You used angle, I used conduit. One thing about string alignment is that the alignment specs are supposed to be taken from the outside of the tire, where the tread is, in the center. If you take it from the rim, you are going to end up with more actual toe-in than you are seeing on your measure (the further out you go, the more you get). I did the math (triangle basically) and found that on 235/40/17, measuring from the rim gets you 1/3 less of the actual toe. Meaning, if you measure 1" of toe at the rim, it would be 1.33" at the tire (using large number to make example more clear). Also, the order of operations should be camber, caster, toe, bump. If you do bump, you may want to re-check toe afterwards. Cant remember if you specified that in your write-up or not.

Sorry, can't answer your trailing arm length question. I put my OEM ones on the bunch and marked center to center, measured it, then duplicated it on my aftermarket arms. I MIGHT have listed the length in my build thread but can't remember. Might just post a new thread asking for someone who still has their rear trailing arms off the car to measure them for you.

CU9DZ - Bottom line is that yes, all those mods put extra pressure on the rear control arm bearings. They won't bind up though. You can sometimes find spherical replacement bearings online but if you do, they are extremely expensive ($400+). Many of us have been running with the caster mods without issue.

[Harley818]

Hindsight,

Good to know about the correct order, but with my double check method, I think I took care of that and didn't see any measurable variation.
Next time, I'll do the toe in with an angle across the width of the tire so i can measure it at the tread distance. good point.

Also, I'll try the caster method you mention. I have my own slip plates, two pieces of plastic with grease, so I could try this, if I can determine how to get 15 degrees each way with any degree of accuracy.

Thanks for the review and comments. I think I'll copy and post yours at the bottom of my process so others can see your comments in the same location.

[Canadian818]

I used a Longacre Caster/Camber tool, and highly recommend one. There instructions list measuring at 20 degrees, and they've machined the outside part of their gauge to 20* on each corner. All that's required is to line up said edge to your alignment string, zero out the gauge, then turn the wheel until the other edge of the gauge lines up, then look at your caster bubble. No need for drawing lines, protractors, or fancy turn plates.

[CU9DZ]

OK. I'm confused.
The hurricane bracket on the back of the lower control arm has a straight wing and a curved wing. The curved wing is about 9 mm longer the straight one. Currently my bracket has the shorter straight wing facing out. If I rotate the bracket 180 degrees the longer wing would be facing out and would push the pivot point inward not outward. the idea is to move that pivot out in order to push the lower ball joint forward.
Also once the splash panels are riveted in place the whole back end of the control arm is very difficult to get to. The only easy thing is to shorten the back part of the upper A arm.
Dave

[flynntuna]

I used a Longacre Caster/Camber tool, and highly recommend one. There instructions list measuring at 20 degrees, and they've machined the outside part of their gauge to 20* on each corner. All that's required is to line up said edge to your alignment string, zero out the gauge, then turn the wheel until the other edge of the gauge lines up, then look at your caster bubble. No need for drawing lines, protractors, or fancy turn plates.

Which tool did you use? http://www.longacreracing.com/products.aspx?itemid=2444&pagetitle=Alignment+Tools

[Canadian818]

Which tool did you use? http://www.longacreracing.com/products.aspx?itemid=2444&pagetitle=Alignment+Tools

Part: #78260