Catalytic converter and MPG's?

[brianjbeach85]

Does the catalytic converter hurt MPG's that much? I am trying to decide between a 5' MBRP Cat back... or 5" turbo back... My biggest concern is come inspection/emission time obviously the cat back is best way to go, but is it worth the $260? or should i spend the extra 200 for TURBO back and get most gains... the turbo back is 5" with a 4" down pipe... Thanks for help here.. trying to buy this system as soon as i can get educated feedback from you pro's out there.

 

[JohnBoyToo]

from all I've heard the cat is pretty hi flow....
the muffler is the bottle neck in the exhaust...

A turbo back will give u the best flow, but will you be able to tell the difference ???
maybe....

All testing I've seen is a 5" exhaust is over sized unless you are going for HIGH, HIGH hp with new turbo, and high dollars...

a 3.5" downpipe and 4" exhaust is the best of both world's....