Test pipes. Big gains over HFC's?
 

I'll be dropping off my car on the 15th, if all goes well, @ Performance Factory to have my Twins installed. In my setup I got 2.5 test pipes, but am thinking about selling them and getting a set of Berk HFC's to quiet things down a little. How much would I be robbing myself of hp/tq wise? Stock motor (for now) not going to run more than 8.5psi. Set up is in my sig.

I imagine a lot!!!!

Don't go for anything other than 3" DP's

we make a lot of power on 2.5 test pipes. you dont really need to get anything larger unless you plan on building pretty soon. you have nothing to worry about at all....



see ya later this week !!

Has anyone made over 500whp with 2.5" test pipes and stock heads? If so, what kind of exhaust was it?

I'm at 510whp@14psi with Greddy EVOTT exhaust, 2.5" test pipes, stock heads and valvetrain.

Nice! Thanks for the reply. I was worried 2.5" might not be able to, unless there is some correlation between turbo size and tp size.

Anyone think 2.5" TP and Nismo exhaust (Y-pipe design) will be able to hit 500whp?

sure, with enough boost.

at 15.5 psi on stock heads and valvetrain we did 538whp. heat soaked run on 2.5 inch dps. greddy twins. 18g.