Hi my friend has a pretty much stock 01 Auto Prelude. All he has right now is a muffler in terms of performance. He wants 3" piping to go along, but i feel that this is too big. Im pretty sure 3" piping is for forced induction only and will only hurt his backpressure with the mods that he has/will get. Am i right? What kind of piping do you recommed that he gets to improve performance?