Cobalt SS Network - Need bigger exhaust??

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Need bigger exhaust??

So I have a 07 ss/sc that I use for an ice racer and I had a question about exhaust. The car has the zzp stage 3 with 60 lb injectors and a 2.9 pulley tuned for 91. I have all the cooling upgrades and a zzp intake. For the exhaust part of it I have a pacesetter midlenght header going to a 2 1/4” in and out cherry bomb muffler to add a little back pressure and cut down the noise. We put the car up on the hoist today after racing it Saturday and almost all the red paint is burnt off the muffler. Do you think I should go with a 3” instead of the 2 1/4 or just don’t worry about it. Thank you in advance!

the paint will burn off the mufflers, its not really a high temp paint. also, the exhaust on a boosted engine is going to get hot regardless, especially running under heavy throttle in a racing application (even if it is ice racing).

there is some power benefit to going bigger, 2 1/4" exhaust with a 2.9" pulley will be restricting it. 2 1/4" exhaust seems about right for a 4 cylinder, but you have to keep in mind that at 14.5 psi boost the engine is consuming double the amount of air that a naturally aspirated engine is, so you may as well consider it a 4.0l. most people here its usually a toss up between 2 1/2" and 3" exhaust, people wanting a more street friendly quieter exhaust go with 2 1/2", those not caring and wanting best performance go with 3". myself, for a race application i wouldnt run any smaller than 3", unless you are governed by noise limits.

That is exactly what I was looking for, 3” it is!! I was kinda concerned when almost the whole 28” of the mufflers red paint was burnt off and almost all the header paint. I guess it really cooks when you are wide open for 20 laps lol
Thank you!

I used VHT header paint on my turbine housing and it actually holds up really well if you follow the instructions. 2.5 or 3 will be fine but if you arent afraid of the lsj rasp then go for it. Mufflers definitely help.