Hello everyone, I am still learning so here is a dumb question. I have a 71 Riviera and I see TA Performance sells Shorty headers with 1 7/8" primaries into a 3" collector. Does that mean I need to run 3" pipes? Does reducing 3" to anything less counter the effect of headers in the first place? The engine is original but I added a D.U.I. H.E.I. with the original Quadrajet. I have an Edelbrock Performer Intake I may add on, just need to figure out the vacuum ports. I will eventually get the TA Stage 1 heads, the upgraded timing cover for the neoprene seal and better oiling system, a cam from TA as well and the double roller timing chain. I also saw advice on decking the block to raise the compression which I may do as well. I figure I can do all the other stuff first and do the headers last, but I was just wondering. Thanks.
Do long tubes work on the later Rivieras? Exhaust gases cool as they make their way out the far end. 3" head pipes and going to 2.5" exhaust pipes will provide no discernible decrease unless you are drag racing and winding it up to 6000 shift points. Even then, it won't be much.
TA Shorty come with the collector that reduces to 2.5". TA did sale a 3" down pipe that was a direct bolt on to run 3" exhaust system. But like everything else for all Buick related performance parts are no longer availably just like the TA Alum heads.
Check with TA. From what I’ve always read, shortys will reduce low end, long tubes maintain or add low end. Shortys are more for a packaging convenience.
Thanks everyone. I thought (for the 71 Riviera at least) I had to use the Shortys for clearance issues, and to not have to cut and modify parts. I was just concerned with pipe size. Once again thanks for the advice and input.