[cobra232]

ORIGINAL: raz54

I'm not sure on your MPG but if you lower your back pressure too much you will sure lose low end tq. If you stay with 2.25" pipe and keep all the cats you should be OK with true duals.

i have to disagree. first off nowhere in fluid dynamics is the term backpressure exist. it is restriction. secondly of all the cars i have seen dyno'd none have been more that 3-5ftlbs down on torque down low.

you gain more up high which flattens or lengthens the torque curve which can feel like you lost low end but in reality low end stayed about the same while the mid and high gained. it will fool the butt dynoi every time. i know for myself it feels more sluggisg low but it really isn't. the dyno and 60' times can prove it every time.

2.25" is sufficient for the V6. you can gain alittle more with 2.5 and 3" duals but they are not really needed for most. if you have Nitrous or a Blower then 2.5 is fine. a guy over at V6power gained 12-15rwhp/twqe with dual 3" and dual Random technology superhigh flow cats but his car is cammed and ported and polished too and i think he puts down 240ishrwhp NA