blue04gto

I'm about to change from the stock set up and add sweet thunder mufflers and delete the resonators. My question is if i increase the size from the stock 2.25 inch piping to 3inches is that to much? Or should i go with 2.5" piping from the cat back?

Its my first mod, i will be adding CAI as well.

 

BuffGTO

I went to 3" with Stainless Works Headers and it sounds GREAT!



My review:

Review: Stainless Works Long Tubes & 3" Exhaust

blue04gto

Can i get some more thoughts please

johnebgoode

Personally if you dont plan on making any significant changes to the engine, I would stay with the 2.5 pipe. Bigger pipes can hurt your performance. they will sound better, yes, but the end result in a race may not be conducive to a win. The smaller diameter pipe will generate more heat as the gases will not be able to exit as quickly. Most small stock engines rely on that for performance. remember, bigger is not always better....

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707GTOLS2

I remember learning for my old muscle cars that you should only run 3" pipes unless you are touching at least 400 hp, I'm not sure if that applies to the our GOATS but just some info I remembered

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Nor-Cal GOATS
05IBM/Blue M-12
04Olympic White Yukon Denali
Advanced Dyno
www.advanceddyno.com
Tuned the First 2 West Coast M6 GOATs in the 10s

westell

3" will work fine. And if you ever mod up, get more air in and make a bigger bang, you'll want to get those gases out quicker.

I think big ol sewer pipes make the @ss look better

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2004 Onyx Black, M6, Mods in excess of 250 characters excluding BB Code markup

BuffGTO

Well this motor stock puts out 400 crank HP out of the box. Assuming 15% drivetrain loss, thats 340whp. Put some nice headers and bam, your about 365-380whp with just headers & exhaust