Help - which is correct?
Team Owner
Joined: Sep 2001
Posts: 62,119
Likes: 1,725
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Thats normal.
In the various years, GM f'd with the exhaust. In 85-86, I know that they only have one functional. In later years, certain options triggered the dual-functional on each side. Z51 definitely got it if it was offered.
Damn EPA noise regulations.
In the various years, GM f'd with the exhaust. In 85-86, I know that they only have one functional. In later years, certain options triggered the dual-functional on each side. Z51 definitely got it if it was offered.
Damn EPA noise regulations.
Le Mans Master
Joined: Jan 2004
Posts: 7,276
Likes: 3
From: Why are there squished peanut butter cups in my underware?
`85-`87 only one nozzle is functional.
`88-`91 all convertibles and 2.59 auto coupes have the same one nozzle functional standard muffler.
`88-`91 coupes with manual or 3.07 auto trannies will have the "sport" functioning dual nozzle mufflers.
`88-`91 all convertibles and 2.59 auto coupes have the same one nozzle functional standard muffler.
`88-`91 coupes with manual or 3.07 auto trannies will have the "sport" functioning dual nozzle mufflers.
Race Director
Joined: Feb 2002
Posts: 11,599
Likes: 1,053
From: Compound in the Grove, Ga.
2026 Corvette of the Year Finalist - Unmodified
2025 C4 of the Year Winner - Unmodified
2024 C4 of the Year Finalist - Unmodified
2020 C3 of the Year Finalist - Unmodified
2019 C4 of Year Finalist (performance mods)
2018 C4 of Year Finalist
2015 C4 of the Year Finalist
St. Jude Donor '16
Only one functional on a ZR-1
Thread Starter
Racer
Joined: Dec 2000
Posts: 326
Likes: 0
From: Santa Monica CA USA
My friend's car is a 90 coupe with the Zf in it. I have an 89 with a 6 speed. His has only one tip open. Although I have long since replaced my mufflers, my best memory is that both tips on my car were open. I was supprised that a 90 with all the stock hipo stuff on it would have a restrictive exhaust. Just the other day he replaced the stock mufflers with square tipped black sport mufflers he bought off ebay (they are brand name) and the resonance is impossible. He had a shop put in the cross pipe in the y pipe but it only helped a little. He has to go to another set up because the resonance is too loud. Any body want to buy a new set of hi flow mufflers cheap?
