Sidepipe installation - 1966 Big Block

[Robert T.]

While waiting for the body to be returned from the painter, I thought I'd put on my new sidepipes. They went on easy enough, but when I was done I noticed that both sides were not exactly level in reference to the ground. In fact, they drop about 3/4 of an inch going from back to front. Well. knowing that the frame is very straight and level, and that the body and the exhaust shield will in turn be level to the ground, how big of an issue is this. Unfortunitly I won't be able to tell until I get the body back on. Will this angle be hidden by the covers? Is this an expected/normal delta to being level. Not sure what options I have if they are required to be level. Oh well, can any installers of these pipes advise me if this is an acceptable variation. Thanks.

Bob

[Peter M.]

Re: Sidepipe installation - 1966 Big Block

Bob - you did not state if the sidepipes are GM or aftermarket - assuming they are within factory specs - you can adjust the front pipe level at the exhaust manifold by loosening the three manifold nuts and raising of lowering the pipes a the 90 degree bend at the frame point. The exhaust donuts do have a degree of sealing coverage that would accomodate this type of adjustment. Of course the rear is fixed but flexible due to the cushion arrangment. Just be careful not to get the pipes too close to the frame to allow for normal torque flex. Don't forget to use the internal steel donut sleeves. Hope this helps.

[Joe C.]

Re: Sidepipe installation - 1966 Big Block

Bob:

There is always a certain amount of variation involved with the fitment of almost ANYTHING to these beautiful, old warriors. There was no robotic assembly, CNC, and very little QC back in the old days. That being said, there are 2 very critical tolerances here. In order of importance is:

1. There must be a min. 1/2" clearance between the pipes and any body fiberglass composite. (Reference AIM "N14" option section).
2. Once that is accomplished, the exhaust pipes must then fit (somewhat) neatly within the covers.

If you do not observe rule 1 first, then you WILL begin to burn the composite. You have a certain amount of wiggle room (I suppose, maybe ten degrees of rotation) with the attitude of the forward anchor point. DO NOT torque the nuts to the manifold studs until you are satisfied with the alignment, because the engine pipes will take a set. The after attachment point is a slotted, teardrop shaped hole in the frame box section, which allows some side-to-side adjustment.

Be sure that you have both inner sleeves installed, as well as the sintered metal "donuts".

Joe

[Robert T.]

Re: Sidepipe installation - 1966 Big Block

Thanks for the info, guys.

Bob