What size exhaust would you recommend for a NA H22 putting out around 210 at the wheels? Is 2.5" for turbo's only?

 

for that much hp natually u have to have 2.5 inches...test pipe would help too

3inches is for turbos usually

what mods do u have for that much power?

 

balanced and blueprinted engine, 11.6 compression, I/H/E, lightened flywheel and crank, port/polish, type-s cams/pistons, 3angle valve job, bored tb, fpr

and a spoon rad cap

the reason i'm asking is i have a custom exhaust and they screwed up and put a machine bend in it so they're doing the entire thing over. so i'm wondering if I should go to 2.5 or stay 2.25...

noise is a bit of a concern for me tho, i love the way my exhaust sounds now and i don't want it any louder. any other thoughts people?

 

2.5 will flow better. With the cams that should act nicely. However Paul has a point, too much and you'll be losing some. A test pipe would affect the sound for sure, but it would flow better.

My next exhuast will be 2.5. For regular street driving, stick with 2.25 if you like your sound now, going up .25 won't give you THAT much of a power increase.

 

actually the hi-flow cat i have is like a test pipe, dirtylude has the same one and failed emissions with it he had to put the stock cat/exhaust back on to pass...

i'm beginning to think the noise/power ratio may not be worth it to get the 2.5... if it was say way louder but i got 10 more hp then i'd do it for sure, but if i'm only looking at 1 or 2 peak hp, then its probably not, and i'm probably losing more low end that way too, right?

 

yeah, you'll lose a touch on low end, but may gain it on the top. For me, losing 2 hp on the bottom, but ADDING 2 hp on the top, is great. Cause I like taking all the power out of the ban dI don't use and putting it into the band I DO use.

 

You should get a 2.5" exhaust. Get rid of the cat. If you're worried about it being loud, just put a long 3 feet, 2.5" resonator inline with the exhaust and go with a nice muffler like a Greddy.

 

but won't the resonator kill flow? whats better a smaller resonated 2.25 or a longer resonated 2.5?