...other than make sure you don't breathe too much of it?

So.... bought a 92 Si hatch with some "questionable" modifications and I've made it my early spring project to return it to stock spec so I can stay in H Stock.

The car has some no-name header on it right now, no cat, and a hodgepodge of semi-perforated pipe toward the stock muffler and tip. After looking under it yesterday, I'm surprised any gases actually make it to the tip. So, needless to say I'll be overhauling it.

I am sourcing a stock D16Z6 exhaust manifold and downpipe, and will have to put a OEM-spec cat on to be class-legal as well as emissions-legal, but what I want to know is what to do after that.

SCCA stock rules allow replacement of the exhaust piping and muffler after the cat, so is there any performance benefit to be had by going with a larger-than-stock pipe or a freer-flowing muffler, or is it pretty much a wash and I should just throw the stock size pipe and OEM-spec muffler on?

 

i've seen a lot of 2.25" systems on the 1.6l stuff.

i got to believe slightly larger than stock won't hurt but don't go too large.

you might want to end it early and turn it out the side in front of the tire if you can.

will this be daily driver plus autocross?
driven only to the event?
trailered to events?

i've also taken a 8" pipe and turned it down after the resonator (in front of the rear tires) and pulled the muffler at events where i thought another 20#'s off the car could help.

 

Thanks for the reply. This will be a double-duty daily driver/autocross, so I definitely want it to look stock and at least sound somewhat close to stock.

I was thinking about doing 2.25" and a slightly freer-flowing muffler with OEM-look exit under the rear bumper. That way it wouldn't attract any visual attention (not that I'm trying to pull anything over on anyone on the autocross course.. just that modded hondas get too much attention as it is outside the autocross course, and I want to look as boring and not-worth-stealing as possible) .

Good to hear you have seen quite a few 2.25" systems on the 1.6s, that makes me feel a little less like I'm wasting my money going with anything bigger than the 1.75 or whatever is on there from the factory.

 

You should look at an Apexi World Sport 2. Spray it with some high temp black paint for the stealth look.

 

Or even better, look up the Apexi World Sport Noir. It's basically a World Sport 1 that comes painted black (the entire catback, everything) from Apexi.

I have one and I love it. Loud, noticeable exhausts really bug me, but this one has a nice quiet tone and almost looks factory.

 

^^

That doesn't look too bad... I'd like to have a completely stock-looking tip, but for stealth, that definitely delivers.

P.S., nice looking hatch. Is that the rear view of the same car you posted in the "azenis on steelies" thread? Hopefully my hatch looks that clean again someday.

 

The exhaust is a little more expensive than the regular World Sports.

Yes, that's the same car, but this picture was taken only a few months ago.

 

if you want something stock looking then just buy a magnaflow muffler with 2.25in inlet and outlet. then have the rest of the piping pieced together at an exhaust shop. it will sound quiet enough and will look stock.

 

^^

That's kind of what I was getting at. I think that's what I am going to do. Should prove to be quite a bit cheaper as well... more money to spend on shocks and tires!