Restoring 305 TPI 5 speed IROC to factory specs.

Is this the same exhaust as a 305 TPI Z28?

Who supplies factory spec exhaust?

How about GM? My guess is GM discontinued.

Do any performance aftermarket companies make a system similar to factory spec? Any reason factory spec system might suck too much to even consider?

How about NAPA or your basic auto parts stores?

Need advice in order to get this done before Spring driving and show season. Important to get same look and sound that GM intended when these things were new. Thanks.

 

Regarding factory look, diameter won't matter that much. I don't mind bigger than stock (3 1/2??). More important to get sound, muffler size, and tailpipe geometry similar to stock.

 

I got a factory replacement exhaust setup from NAPA last year for my 83 Z28. It was a direct bolt in kit from the cat all the way back to the tailpipes. Can't remember the price or p/n. Very easy to install though. Only thing that was different for mine though, was the fact that the replacement muffler setup was a single crossflow muffler. My original muffler setup was that funky one with 2 small looking mufflers. Other than that, it was all good.

 

Thanks.

I have the NAPA site info in front of me. They show three mufflers:

Quiet flow (probably not it)
Ultra Flow
Super Turbo

I'm guessing Ultra Flow is close to IROC stock. I have faith in NAPA, but not enough yet to have them pick one if there is no other supporting information. Don't want to order/install a system only to find it's no even close.

Have you ever heard your new exhaust compared to a factory IROC?

 

That vivid blue pearl is awesome.

 

IMO, the exhaust sounded pretty close to stock. It still has that nice low rumble to it. But that's just my opinion & mine is an 83 Z28 with a 305 quadrajet. So it's slightly different than yours. Good luck on your search. Oh, and thanks for the compliment on my car.

 

Sounds like the NAPA is Walker exhaust. That's Dynomax in the performance kits. I just installed a Super Turbo complete kit in my 88 and it is probably close to factory. Not loud but has a nice deep tone to it. Fit very well, no problems. Price is reasonable, about 170 at Jegs. Ultraflow is a bit louder.

 

You can always try a GM dealership...

 

Ive seen them on ebay.

 

You could just ask someone on here if they still have their stock setup. I'm still getting ready to buy my exhaust, and if you want I could ask the guys installing it to save the catback for me. I've got an 87 too. It just won't look as pretty as a newly purchased one.

 

That is a generous offer. Currently have a nice looking muffler (externally rust free) with 22,000 original miles, but as long as I'm getting the pipe between cat and muffler I should do a new muffler, too. Experience with other cars is that muffler won't have long to go. Should go new all the way. Thanks anyway.