I always hear people saying if you get rid of backpressure you lose low end torque.... I dont see why though, I figure as little backpressure so long as you dont burn valves and keep the pipes the right size so the velocity is high. Maybe i am wrong but would liek to know for sure.

 

backpressure and low end torque are not realated! PERIOD

The less backpressure the better!

I'm not really in the mood to get into this same thing for the 10th time, it gets old.

Look on LS1.com or LS1tech.com in a search with my username and backpressure I'm sure I have wrote something there!

Bret

 

You might only want a little back pressure if your runing a crappy little stock cam.
How it helps low end torque,
It restricts exhaust flow sliding your torque curve back on the rpm scale and to a lower # also lowers Hp.
The only thing back psi does is make your torque peak lower.
If you want a Hp machine you want all most no restriction with some good exhaust velosity, if you want a 3600 rpm dump truck engine get some back psi.
But I have seen some wild SBC's lose power ( Hp and tq ) when going from open 1 5/8 to 1 3/4 open headers with 3'' primarys. Open is better 90% of the time.