Well I'll take a guess and say I prolly have the most displacement of anyone on this board and I have dual 2.5" cat's into a Y and a 3" cat back to the muffler. Its not overly load with regular driving but if I rug it then it is abit over kill. But it is still way quieter then the kid next door that owns a saturn with the "fat can" on it. That guy comes and goes all night long and it drives me nut's, to make matters worse he just has to rug it everytime he takes off.
