3" downpipe power increase?, about how much? Options

[easternpiro1]

Hi guys, Ive been wondering how much HP increase do you get when you add a 3" downpipe to your turbo setup? ive been told in the past at least 10hp, but before making a thread i decided to do some searching....

http://www.mr2oc.com/showthread.php?t=2714...horsepower+gain

and now I have a headache...

on our 3s its obvious that a wider diameter exhaust makes room for more power, but ABOUT how much typically?

I actually read 98% of that thread, and while VERY informative, i didnt get a question answered after all the searching.

anybody know the answer?


cheers!

[Rav4Race]

Hi. In my Opinion;

Having a bigger downpipe will just help your engine to breath easier, in other words, a better flow compared to stock. But having a 3" downpipe will just give your engine more potential to make more power later. To make more HP, an optimum use of your new downpipe, would require an aftermarket manifold and a boost controller. Because such modifications will make u face other issues like boost creep or overboost and fuel cut. You may also like to get a better turbo and if possible a standalone ecu so that you take the maximum advantage of your new modifications. Such modifs should get u, I'd say like 50-60 HP (all together)!!!
But getting only the downpipe may only allow like 4-5 hp.
Downpipe + manifold may get u around 12 hp.
Downpipe + Manifold +decat may get u around 15-20 hp.
Downpipe + manifold + decat + new turbo + ecu may get u around 50 hp.
Downpipe + manifold + decat + new turbo + ecu + injectors may get u around 60-100 hp (depending on your tuning and engine capacity).

You may also modify step by step like i am doing, take ur time and get the maximum of your investment in the future. But you will need to tune your boost.

On my side i have bought a 3" downpipe and a manifold + decatted. But I had to tune the engine since I was reaching fuel cut and overboost on only 4500 Rpm.
I am taking my time but will surely get the other modifications as soon as i get some $$$