2.5" -> 3" performance upgrade

Hey,

Im just curious to see how much of a power increase/spool increase from a 2.5" catback (resonator also) to a full 3" to high flow muffler.

Currently i got 443 and 300 at 17psi on a 6265 .82exaust on conservative timing, but i know there must be some extra power to free up by swiching over, or is there?

:turbosmiley:

3" gain in the midrange and will produce more torque than 2.5"
it been said over and over "either go big or go home"..LOL

i have a go power 3" exhaust

sounds good. I need to build a custom one, imleaning towards a K teller piping kit with a magnaflow muffler.

http://www.honda-tech.com/zerothread?id=1530154&page=1

Now, this is a different motor with a different setup completely. Those gains are pretty steep and a bit tough to believe. Regardless, my main point of posting that thread is to show you that a 2.5" to 3" exhaust upgrade is a very big deal on a turbo 4-cylinder setup. And a K20, IIRC, will rev higher than an H22/23, therefore a larger exhaust is even more beneficial.

:thumb:

3" exhaust, especially turbo-back, works GREAT for top end. You'll definitely gain at least 20whp from the switch alone. The less restriction the better on a turbo setup.

:dance:

now i have to get to work

What are your options? Most likely custom I assume?

yup have to be custom, which is no problem. I was leaning towards a k teller with a magnaflow muffler and vbands, but my friend has a full 3" on his hatch back that said i can buy. He basically bought all the bends, cut and welded them together.

442whp and 300 trq. Id like to see 460 and 330 torque. My ultimate goal was to touch 500 on pump. Dont think it'll happen.

Quote:

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Originally Posted by boosted_teg

yup have to be custom, which is no problem. I was leaning towards a k teller with a magnaflow muffler and vbands, but my friend has a full 3" on his hatch back that said i can buy. He basically bought all the bends, cut and welded them together.

442whp and 300 trq. Id like to see 460 and 330 torque. My ultimate goal was to touch 500 on pump. Dont think it'll happen.

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The hatch exhaust will be a different. If I were you I'd go the kteller route. I made my 2.5" like that when I was all motor. And then I got a steal of a deal on a thermal r&d 3" and I gained power just all motor. So I know a 3" will give you more. Lucky you that you have a turbo to muffle the noise. Mine is just raw. Lol.

What did you end up going with?

IIRC He went with a custom 3" exhaust