Hey All,

what is the size of the intermediate pipe on the exhaust of a 93 Z28 ?

 

2.75".

 

Wow.. If they intermediate pipe is 2.75 ... how much performance differnece is there between buying a 3" catback vs just bolting on a free flowing muffler?

 

I honestly have not seen much improvement in pipe diameter, just muffler swap from stock helped alot.

 

Cool shon

What muffler did you go with? I see alot of people slamming flowmaster, but i havent seen any cfm comparisons between the other mufflers.

 

I like the Aerochamber muffler, see straight thru it and it is not loud.
I do not like Flowmasters on LT1s.

 

would you say the flowmaster is louder than the hooker?

 

Yes, the blowmaster is a lot louder than the Hooker, but flows less.

 

if you dont have to go to emmisions and have them hook up the sniffer thing on a tailpipe, go with an adapter from 2.75-3" and then do a 3" bullet and turndown before the rear axle. with stock exhaust manifolds and cat it sounds INCREDIBLE. its so deep and different. i loved it on my 93. just something to think about, but keep in mind wont work for emmisions. other than that i heard the hooker muffler sounds good and puts out the power.

 

It's worth it to go with a true 3" cat-back but you might want to get a true 3" high flow cat as well. On my old 93 Z28 Indy Pace Car I ran a Borla y-pipe with a high flow 3" cat. The Borla y-pipe is 2-3/4" pipes coming together into the single 3". It definitely made a difference. But I also had a supercharger so it's tough to tell what the difference would have been with just the exhaust alone. I would get the Hooker or Pypes cat-back over the Flowmaster.

 

Why wont the 'sniffer' work with the bullet muffler and turn down?

 

because it turns down right before the axle and that huge setup they have to stick on there wont fit and theres pretty much no room to get it on, also it wouldnt work with the rollers they go on.

 

I have Flowmaster and was disappointed when I first installed it. However, since adding my headers, it's much better. But as others have pointed out, others flow better.

 

My 93 stock exhaust, measured with a dial caliper shows that the stock intermediate pipe to be 2 and 5/8" out side diameter where the pipe enters the stock muffler. Pretty small! It most likely is 2 and 1/2" inches inside. GM had a Performance exhaust system for this car, I don't know if it's still available or not. Hope this helps! 93zTED

 

Inside diameter and outside