aight i am totally lost on backpressure. do u want it or not?? i have heard that u need it and that u dont. which is it?? also how much would u want? i ran my car for a while w/ no muffler and it seemed faster then w/ my magnaflow muffler. however at the same time i have also had just a manafold and a flex pipe with no cat, no resonator, no muffler. that set up was horrible b/c there was absolutly no power in the car. and reading all the forums i see something bout velocity. what is the best set up, reguardless if it is illegal(not saying i am goin illegal, just wondering).