Newer exhaust?

[GTU89]

Okay, my GTU has the stock exhaust, which is tiny. Several members IIRC said that the newer style exhaust is bigger, is there a big enough difference in size to make any difference at all? I imagine with how restrictive the older exhaust is it would make a bit of a difference, but I am not sure. The cat (was gutted before I bought it) is starting to leak a bit, and the weird put-put exhaust leak sound sounds bad, so I may just see if a junkyard would sell a newer style exhaust cheap, instead of just welding wherever the cat is leaking.

Another question, I'm assuming the bigger exhaust would come off of a plastic gas tank Beretta, would that pose any problem with my older metal tank?

What years are the best to get the exhaust system off of? And is there any difference in the manifolds throughout the years?

[ronaconda]

I did this very swap and it involves ALOT more than just swapping to the newer style exhaust. Little things that had to be changed was the upper radiator hose had to be put on backward (will not work with the stock air box), a different transmission dipstick (will not mount to the head with the newer stuff), and i had to go to the longer style shifter cable setup on the early 90's transmissions (the 89 shifter cable and bracket will work but it interferes with the lower rear heat shield). A custom downpipe will also need to be fabricated.

[GTU89]

I did this very swap and it involves ALOT more than just swapping to the newer style exhaust. Little things that had to be changed was the upper radiator hose had to be put on backward (will not work with the stock air box), a different transmission dipstick (will not mount to the head with the newer stuff), and i had to go to the longer style shifter cable setup on the early 90's transmissions (the 89 shifter cable and bracket will work but it interferes with the lower rear heat shield). A custom downpipe will also need to be fabricated.

All that for just the exhaust system? Like, without swapping manifolds? Or would it be pointless to do it without swapping manifolds?

[ronaconda]

Yep, all of that just to make sure everything worked and I would have no problems. The 89 top radiator hose comes WAY too close to the newer style stuff and flipping it end-for-end moved it away but it will interfere with the stock air cleaner box. I have a CAI so this wasn't an issue for me. The trans dipstick i was able to get from a Lumina/Grand Prix with the 3t40 trans and bent it to fit. Those tubes mount to a boss on the block rather than the head. I swapped the manifolds and the x-over to the newer style...i think i got them off an early 2000's Grand Am. I'll post pics if i have them.

[woody90gtz]

I didnt think the exhaust was any different size? My 90 GTZ and 95 Z26 both had 2" exhaust. The later stuff with the metal tank (95-96 I think) is a little better for rear axle clearance. I am running a 95 tank & custom 2.5" exhaust on the 91.

[ronaconda]

IIRC the "newer" style manifolds flow better, especially the "header" style rear manifold. I am as well running a custom 2-1/2" exhaust.