Exhaust improvement question
 

I understand that making a more free flowing exhaust will help the performance of my engine (and more important, the 1JZ I would like to put in it eventually.) That said, I do NOT want to have a car that is loud or has one of the obviously aftermarket tailpipes one sees on all the low end Civic/Neons out there; in fact, I want for it to require someone pretty knowledgable about Supra to know that my car is anything but stock.

The other day I was driving next to a Dodge Stealth (the driver was admiring MY car, btw) and noticed that it has two sets of tailpipes where my Mk III only has one. I know that engine is a 6 (though a "V", not and "I") so I wondered if it is possible to double my outbound exhaust channels as well. I realize I am probably stuck with a single exhaust manifold coming off the head but if I could split into two immediately would I realize a similar gain to what I would see with one of the bigger diameter pipes?

Well my exhaust was rusted out when I got my car so I replaced it and it isnt load at all really but the tip is huge. But HKS is a well known brand and people will have to get close to even see if it is a actual exhaust and not just a muffler and a tip. Now to your next question being a in line 6 and the fact of where the gas tank sits I am sure you would be hard pressed to put duals on your car which is fine a good exhaust will flow just as good as his duals. Stealths kinda suck anyways they reall didnt have a large market of mods out there for them. Also being they are a mitsubishi 3000gt and mitsu engines like the older 4G63 have lots of problems stick with a toyota and he should also. Back to the exhaust a 3" inch exhaust for your N/A engine really doesnt help it much but when you do the 1JZ upgrade it allows you a lot of potential. HKS makes a lot of exhausts for the N/A though like the high power and the sport that look kinda like factory. Turbo and none turbo if it is for the mark 3 they all fit also if your emmisions laws in your state allow it put a test pipe in it more fun that way.

What is a test Pipe:

you can put a dual tip on ur supra thats what im going to do. I saw a dual top exhaust in a super street mag on a mkiv and now i gotta do it to mines it was just to beautiful. and dont worry it wont be loud as long as u dont gut out your cat keep the cat and u keep the noise down

A test pipe is a 3" straight pipe with toyota flanges that replaces the main catalytic convertor.

And he is right, having a stock cat will keep the loudness down, along with the nasty'ness.

You have a non-turbo so unless it was a cali car when it was sold brand new, you don't have a pre-cat, which is another big time restriction on turbo cars.

where is the pre cat located.

Pretty much right after the manifold just before the exhaust piping bends under the fire wall.

on the down pipe