Exhaust size???

[Newkid]

I have a stock 90 toyota supra. I wanna run a 3" down pipe, test pipe, and rsr exhaust. I was wondering Will this increse power or will I lose it because I'll lose pressure?

[pricematchedparts.com]

You will get more power.. your turbo will creat more then enuff back pressure for you.. What kinda downpipe and cat Delete are you going to go with?

PMP

[DarkTemplar]

you will gain power. what kind of dp r u trying to get?

Dark Templar

[1caintegra]

big motor+ plus turbo+more exhaust flow=gain

[Newkid]

haha thanks btw Im getting Bic ddp and their test pipe

[Wolfe]

should pick up some horses, I am running a 3 inch megan with cat delete on my 240

[Porsche944Turbo]

With a turbo, there is never a concern for not enough back pressure. You would be surprised at how exponentially back pressure becomes in the higher boost levels.

On my car, at 20psi, the back pressure is like 60psi. Most of that is due to a less than perfect head design, but you get the point.

Also, with most turbo, getting the cat out is the biggest gains people see in going to bigger exhaust; at least on a mostly stock car.

The rule is usually 1" for each 100hp up to about 400 or so; i.e. 250 hp = 2.5" 400hp = 4"

[ebxr8240]

On a 4.0 turbo we gained 75 rwkw by fitting 3.75" off turbo down to 3" on a 10 " long collecter.. It lets the spinning gases time to flow down pipe ..
Plus it made for more boost response...

[Intense_Motorsports]

as long as your wastegate can handle it run as big as you feel comfortable with i'm about to build my new 5" downpipe that will go to my 4" exhaust. gotta love it!

[Newkid]

Cool but now I have a new...well question?

I done the 3" cat back, a muffler shop did it. Weird thing is that its quite, I mean quite like stock? My old exhaust which had holes and rusted was louder than this ( little hole so it wasn't that loud at all). I wanna know why is it so silent?