Hey i was thinking about running dual exhaust on my car. I was gonna get a 4-2-1 system and cut it off b4 it turns into one and run two exhausts. Each with thier own resonator and everything. Ive heard some people say that dual exhausts on imports can actually decrease power? HOw could it decreas power? I dont know if those people know what they are talking about. I know our cars dont need duals.....but the look and sound quality would kick ass. Does anyone know?

This post has been edited by BigJ: Oct 3, 2004 - 4:30 PM

i mean your decresing exaust velocity and therefore losing torque especially with the little 1.8l. if you going dual exaust i would make your pipes any bigger than 2".

-recneps+Oct 3, 2004 - 10:47 PM

yeah i meant not sorry bout that.

if you go 1.75" like stock then you will be fine, with an aftermarket muffler

Yeah thats what someone told me. That running duals would cause me to lose too much back pressure. Ive never messed with exhaust systems much. I always thought the easier you made it for the exhaust had to flow the better. So i could just do the 4-2-1 with a 2 inch exhaust and split it off close to the rear to 2 mufflers with 3 inch tips. Set up a mock dual system. You guys think that would be ok? Ive never messed with exhaust systems much. I always thought the easier you made it for the exhaust had to flow the better.

This post has been edited by BigJ: Oct 3, 2004 - 7:49 PM

thats no good, you'll get uneven "smoking" or the exhaust will come out uneven and it will make your car sound bad,,,,,,,,just ask coomer, or supersprynt

Back pressure being positive is a myth, as for dual exhaust, there's been many a discussion about this, I'm sure a search would turn up something.

Basically, what everyone told you (except for back pressure) is right; do a search and you'll see why.

Even if you had enough power to merit dual exhaust on our cars; there's no room for the piping.

i got dual exhaust on my car...i admit that i did lose a tiny bit of back pressure...but my mid to high end performance has gotten better...especially in 2nd and 3rd gear...looks nice to with the bumper i got customized...

Backpressure bad... velocity good. The goal is to eliminate back pressure while maintaining good velocity...

ahh but on our 7afe's we need some back presure. and dont go dual exhaust its pointless. also ive seen like 1200 hp supras with single exhaust.... its just better.

You dont NEED backpressure. It is bad for the engine, not good.

I dont recommend the dual exhaust, but if you want I have a dual exhaust setup I'm selling

Like super, like kwanza said; you never need back pressure, it's ALWAYS bad.

What you WANT is gas scavenging; which is the ability of gas particles to latch on to one another and pull themselves through the engine. The larger your exhaust, the further apart the gas particles (since they're like goldfish, and will fill to any available space). Backpressure only hinders gas scavenging, it's like a red light. You want to eliminate backpressure while maintaining a good size for gas scavenging; and later on exhaust velocity. That means you don't go as big as you can go- to get the right size for a dual exhaust you'd have to have rediculously small piping.

i was thinking duals on my 3sgte swap, but i have decided to go with single 3" mabey a little smaller, and i am going to strongly suggest not going with duels on the 7afe, theres no point.
i have gotten to the point after looking at many exhaust systems that i like the single look better, duals on the celica looks too bulky anyways, mabey on a vette or something but when were talking about a small car and large can mufflers its too much imo

Yeah....I wasnt gonna run the duals until i did my 3s swap......I dont think im gonna do it though. Another reason I was thinking about it was b/c i think im gonna get the Pakfiefer kit and the rear bumper has openings for duals. Didnt wanna have an open hole there. But the car in the pic has single exhaust and it still looks good. Thanks for your help guys!

Looks cool, but really pointless, 4cyl engines really dont gain from this nd its not even real dual its just dual mufflers not exhaust.

Get a 6 or 8 cyl, go dual up to ying yang but for real just keep it 2.5 - 3'' single.

Yeah what I've said before is that dual systems were developed for very big 6 and 8 cylinder engines, esp. V8's. Putting a dual system on a celica (unless it's heavily modded) is so overkill that it's stupid, but if you like the look, why not.