I accidentally posted this question in the Wanted section, so hopefully it makes sense here. New guy!!

First time 3rd gen owner here! I just got my 86 Z28 LG4 5-speed yesterday. It has a cobbled up mess of an exhaust system that I need to take care of right away. They y-pipe was hacked and welded into a really terrible full dual exhaust that is about 3" from the ground. I don't have any need to upgrade for power, etc., just to get it back to stock or close to stock. I have other cars I can race, this one is just for cruising. If I had a stock LG4 y-pipe I would start there and work my way back with stock 2-1/4" exhaust. I don't, so should I put a wanted ad for one, or is it easier to swap manifolds and get the larger HO stock y-pipe that is available and run the larger exhaust? My goal is to be back on the road as quickly as possible with as close to stock setup as possible. Thanks for any opinions!!

 

My last 1986 LG4 I took Sofa's advice and I threw away the complete stock system and bought a used large stock Y-pipe from Frank's Pontiac Parts from a LB9 or L98 with a 3 inch outlet. I added a 3 inch stock replacement catalytic converter (Catco or MagnaFlow) hung by the stock hanger. Then I added a Flowmaster American Thunder 3 inch system. Beautiful sound I liked. Then I threw away the 305 and built a 355 L98. Shazam! Wonderful!

The one I have now is a LB9 305 that came with a horrible cobbled up Y-pipe. This time I tried the MagnaFlow stainless steel Y-pipe with 3 inch outlet. Got a 3 inch MagnaFlow stock cat and finished it off with the MagnaFlow stainless cat-back system. I like the sound and much quieter interior noise level.

There a some higher flow cats out there but I went with the easy stock fit.

 

I have a pair of L98 manifolds and a 3” Magnaflow Y-pipe in PHX if you’re interested. Knocked .80 off of my LU5 with a catback.

 

Are they Corvette L98 exhaust manifolds? (Center outlet,not rear outlet F Body manifolds)

if Vette ones, how do they fit?

 

No. They’re F-body L98 manifolds. This is a thirdgen site 👍 Y-body manifolds won’t come anywhere close to fitting a thirdgen.

 

Oh! A Third Gen site? I’ve only been here 10+years! I’ve got my eye on a 92000 mile corvette L98. Complete, for my 89 IROC Z VERT. Mike

 

10+ years? I’ve been here for over 22 years under various usernames/accounts. Not sure what that has to do with anything. You asked about Corvette manifolds, which I never mentioned in my reply. I answered your question. They don’t fit.

 

looks like I have been here 17 years. Ease up on the coffee, Buddy!

 

I don’t drink coffee rube. Did you really come back to this thread just to have that as your response? Are you sure you’re not 17 years old? Let it go, capisce?