A good metal matrix cat has no back pressure to speak of.... I've flow tested several on a flow bench. Its kind of a myth left over from the old pellet cats of the 70's and 80's, and the crappy eastern import ones with ceramic cores and cardboard liners.
Just sayin...
Dave __________________
Dave - PDX
1995 318ti - Active Black and Tan.
2005 330xi - Mtech 1 - 6spd - Orient Blue/Black |