wadzii

you wont loose any power anywhere, 3 inch exhaust will pick up power from idle to redline

manuelisfun

Why go 3" when you can go 4"? You wussies.

But anyways, I think I read somewhere that too big an exhaust could lose power because of exhaust gas velocities or something.

Actually here, but I'm also sure I've read it somewhere else as well.

wadzii

in theory yes, you can loose power but in practice going up to 3 inch dosnt loose any power at all.

osnap

Well I'll be damned - my mistake. I've always heard that anything over 70mm on a mild N/A F20/F22 will definitely lose power. Seems those sources may have been wrong.

fireball

can anyone post a dyno chart , showing the benefit of goin 70mm to 76mm ?

CarbonYellowJ's

the only thing you will lose is your hearing if you dont get enough mufflers You will gain power in all area's of the power band. IIRC there was a shop that tested a few different diameters and they found open head produced the best gains (albeit redonkulously loud) so the less restriction after the header the better.

CarbonYellowJ's

the gain will be more about the choice in mufflers/resonators as opposed to the increase in diameter. If you have a 70mm that you like the sound of then I would stick with it.

CapoArgentino

People that claim 3 inch piping on NA F20C/F22C produces gains or not is FAIL w/o dyno proof.

Vitt

Well, I'm buying one and will put a quieter muffler on there. Not sure when I'll get that done as I am too busy with work and have other projects for the car (suspension install). When I do I'll keep you posted, but I'm not sure I'll do a before and after dyno.

CapoArgentino

^^ After dyno is all thats needed Thanks man,