3" cat? [Archive] - SR20 Forum

: 3" cat?


NXTremeSE-R
03-07-2002, 02:38 PM
ok, in the continuing saga of my cat q's....

i was thinking of going with a 3" inlet/outlet cat. i know it doesnt matter that much on the inlet side of the cat, but would there be a problem with going from a 3" opening to a 2.25" opening on the outlet side? meaning, since the gasses are going to be moving from a 3" opening to a 2.25" opeing, is the abrupt diameter change going to hurt performance at all? i figure that it might cause some turbulence of hitting the sides of the opeining of the smaller pipe, but if its not a big thing then i wont worry about it...