Exhaust advice, how much performance can be gained by a 2.25 exhaust Options

[97celiman]

so i want to keep the stock 5sfe 2.2 and just see what kind of decent power out of it...i plan on turboing it eventually but id like to start with the basics...i.e. exhaust i dont really want a resonator and i want a full exhaust from the headers back does anyone have any suggestions...should i go with 2.5in piping and do i need an aftermarket cat? i plan on doing aftermarket headers but want the exhaust first or do i need to do both at once...thanks?

[Euphoria]

I'm getting catback exhaust first then going back later for headers and highflow cat, apparently you need to change stock cat converter to put headers in. Anyway for a GT 5SFE I think 2.25 is the way to go as thats what everyone on the forums has said.

[SoDo]

Would the ebay header work with this set up?

[Galcobar]

Sorry, but I have to step in on the resonator question.

A resonator is not a muffler. It is not a baffled muffler, such as what you'd find on your stock car. It is not a straight-through muffler packed with sound absorbing materials, such as you'd buy from MagnaFlow.

A resonator is an entirely different form of noise suppression. Where mufflers either slow the exhaust flow down (baffled) or absorb the noise (insulated), resonators use sound cancellation. They are echo chambers designed to bounce sound waves into each other, so the two waves cancel each other out.

Cars as a rule come with a resonator somewhere under the body, not a secondary muffler. Even round mufflers are not resonators. Here's how to tell -- tap it with a fingernail. A muffler will absorb the vibration and produce a dull response. A resonator will ring like a bell. Just because a muffler is round and goes below the car does not make it a resonator.

It is the lack of a resonator which is often responsible for the annoying buzz of poorly done aftermarket exhausts. Mufflers will significantly lower the volume and somewhat smooth the tone; a resonator will somewhat lower the volume and significantly smooth the tone.

A resonator can be purchased from just about any reputable exhaust shop or supplier.

When planning my exhaust, I chose a MagnaFlow straight-through oval muffler, a MagnaPack straight-through round muffler and a CarSound catalytic converter with a resonated core (a combined high-flow cat and resonator). Lots of sound suppression, good tone moderation, and low flow impairment. Never did buy it all -- few other things came up -- but it priced out well from hottexhaust.com