dirty exhaust pipes and clean ones, too

[aoriii]

I was doing some work on the coupe this weekend and noticed that 2 of my 4 exhaust pipes were clean on the inside of the pipe. The 2 innner pipes showed no carbon buildup at all (odd for an 18 yr old car, I think), so I started it up and felt the exhaust, but there was no exhaust output from the 2 inside pipes?

ox xo

o=exhaust
x=no exhaust output

is this normal?

 

[JT ZR-Won]

My '85 had the same thing from the stock tips. It was almost as if they added dual tips for looks because it only comes out one port on the muffler. Kinda strage.

Jay

 

[Ken]

It was almost as if they added dual tips for looks because it only comes out one port on the muffler.

Guys, I've been trying to re-find that information for years! I know I read somewhere that the inner two outlets on the regular mufflers were dummy tips, and that the ZR-1 & ZR-2s had all four openings functional. Trouble is, I have not been able to relocate or remember where I read that. Every now and then I try again, but so far no luck. It was true, believe me, that some mufflers did not exit through all four openings, they only exited through two outlets.

 

[Vettelt193]

yes, very true.... a quick fix as far as looks go is high temp spray paint.... flat black grill paint works best.... just spray it inside of the non functional tips and they will all match

 

[fast.asleep]

Ken,

I think you meant Z-51 and Z-52.

(All four tips are functional on my '87 Z-52)

 

[Ken]

:duh I'm soooo embarrassed!

Thanks man!

_ken :L

 

[vader86]

Yes some genius at GM decided to not always make the 4 tips functional.

I have an 86 Z51, only the outer ones function. In later years it depends on the optioning as to whether they work or not.

Stupid idea, in my opinion, to make 4 outlets and only have 2 work.