exhaust revisited

[yahrt]

I am running a BP 347 with FFR headers and pipes. I posted yesterday regarding my passenger side exhaust pipe opening pointing down 15 degrees while my drivers side opening is perfectly vertical. Engine is level. i just did some more measuring, putting a level on the 4 pipes running along the body right before they merge gives an angle of 67 degrees on both sides of the car. It almost seems to me that the passenger pipe has a manufacturing defect. Does that seem possible?

[Jeff Kleiner]

Give us a couple of photos

Jeff

[yahrt]

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[yahrt]

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Bear with me, first time uploading photos, this is the drivers side

[yahrt]

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Passengers side, the angles are closer side-side on the quad pipe portion, my son wasn't holding the level very steady, again the real issue us the difference in the openings at the end of the pipes

[yahrt]

I am either not explaining things well or people think I am crazy (entirely possible). To convince myself that that the pipes are indeed not mirror images of one another I removed both and laid them side by side. It clearly shows that the angles of the exhaust openings are not the same. Does this look right?141795141795141796141796

[Norm B]

You’re not insane. Mine was the same before I modified the exhaust and turned both ends down 30 degrees. Never really noticed before. It’s a little hard to see both sides of the car at the same time at a close enough distance to notice.

Norm

[yahrt]

Posed the question to FFR, the response was "The sidepipes are not supposed to be symmetrical. The engine is offset in the chassis to the passenger’s side, making both the headers and sidepipes different from side to side. You can proceed with installing them", this doesn't really solve my problem. Could someone with a completed car, 302 block FFR pipes and headers, measure the angle of pipes on both sides of the car as shown in this picture and report back? 141844141844

[TMartinLVNV]

I don't think that you will get the answer that you want. There is nothing symmetrical about these cars. I have not measured the angle of the exhaust pipes and I'm not gong to. I stood back, looked at the right side, and placed the pipe where it looked best. I did the same thing with the left side. Honestly, I could not tell you off hand if one outlet is at a different angle than the other.

[yahrt]

"I have not measured the angle of the exhaust pipes and I'm not gong to."

Thanks for the obstinate announcement that you will not be helping me out.

My goals are simple, to understand and to be sure that I am assembling properly. If I understand, the angle i refer to above should differ by 15 degrees side-side and I will feel comfortable proceeding. If that is not the case then I still have an issue to resolve before proceeding.

[edwardb]

OK, here's my takeaway. The pictures help because I sure didn't understand what you were describing before. The difference of the angle of the quad pipes (23 vs 27) of only 4 degrees isn't significant in my opinion. It is true because of the angle of the headers (engine is closer to one side than the other as Factory Five said) you could end up with a slight difference. Because you have the ball socket headers, seems that could be adjusted depending on the actual height of where the pipes exit the body from side to side. I'd be checking to see if they are about the same side-to-side. And adjust the body cutout if necessary and if you think it helps. If you end up within a few degrees one side to the other it's OK. In my opinion.

As far as the angle of the tips, those are clearly very different and can't be accounted for because of differences from side to side. I personally haven't seen that before. And isn't in a range that can be adjusted. Just plain assembled wrong in my opinion. Between you and Factory Five to resolve. Worst case could be repaired by cutting and re-welding. But I agree something you wouldn't expect to have to do with new parts.

I do agree with some of the comments that you can go crazy trying to make everything perfectly symmetrical. These cars are not. Probably not what you want to hear, but the way it is. Sometimes necessary to put away the precision measuring devices and look with your eyes. Decide what really matters. And also what you can see at one time. Differences in one side are often not visible at the same time as the other and not normally seen. You also might want to tone down a bit if someone doesn't give you the answer you're looking for. Good luck.

[CraigS]

I see you have shiny pipes. Are they polished stainless? If so it would be fairly easy for someone to cut, rotate and weld back together. And then some polishing. Another thought comes from EdwardBs comment,
"Because you have the ball socket headers, seems that could be adjusted depending on the actual height of where the pipes exit the body from side to side. I'd be checking to see if they are about the same side-to-side. And adjust the body cutout if necessary and if you think it helps. If you end up within a few degrees one side to the other it's OK."
Almost forever it has been common to need to adjust the body opening to a different height left to right. If you were to open one of yours a little higher could that help allow some angle adjustment?

[yahrt]

thanks Edward, Craig, and everyone else for the constructive comments, I understand now and am confident moving forward, looks like three options, modify the pipes, use a wedge, or cut the opening much higher than I would prefer. The discrepancies I noted don't seem intuitive from a design perspective,, I still don't understand why the pipes are engineered/designed to introduce this issue when a simple redesign/rotation would resolve the issue.

[Jeff Kleiner]

You got my curiosity up with this. The only car that is here with the pipes on currently is my own which happens to be a 5.0 Windsor with FFR 4 into 4 headers (Hooker) and steel pipes. Measuring across the top two pipes I show 27 degrees driver’s side and 29 passenger side. The exits measure 7 degrees down from vertical on the driver’s side and 9 degrees on the passenger side. And for what it’s worth in all of the 14 years that I have had it not once have I ever thought that anything looked “off” :)

Cheers,
Jeff

[yahrt]

Jeff seems to have confirmed my observation, my measurement across the two pipes is within a few degrees and yet me exhaust opening differ by 15 degrees...to me this means my passenger exhaust is "off"

[Avalanche325]

One thing that you mentioned is that your engine is level. That is actually fairly unusual. If you start measuring on a Cobra, you will lose your mind. I've been there a couple times myself.
I would find a place that does things like turbo installs and custom work. They will have a guy that does pretty TIG welds.

[Norm B]

As stated in my previous post, I had my turnouts cut off and welded back on turned down 30 degrees as part of a mod to quiet the exhaust. Total cost was about $150.00. Here’s some pictures. The first is the muffler with the turnout cut off. You can see the end of the muffler is tapered and where the turnout was cut off about halfway up the taper.

HTH

Norm