''Project '64 SYT Super Yenko Truck"

[highperf4x4]

Actually the smaller the exhaust the more backpressure you will get to help increase low end torque. A 3" exhaust is really only for very high rpm applications. Much like a tunnel ram. Both of these will kill low end torque but increase hp in the highh end. If you're not going to rev over 6000 then neither one will do much for you. Except make the truck really loud!!