I know you said you had problem with back pressure. Do you think this is a problem with all 3.4s. Is the best way to go with exaust on a 3.4 is just a highflow cat and a catback? No headers

 

I think headers will be very beneifcial, with a Catback, and high flow CAT.


My problems with not enough backpressure is from when I ran an open y-pipe(no CAt no Catback), and I have a cutout, infornt of the CAT, when I open the cutout, I have a loss of backpressure.

But when the cutout is closed and I run it though a Catco cat, and a stock lt1 Catback(2.75 in. i-pipe) its runs alot better then stock and when I jsut had a muffler, but it is not the best flowing setup, there is room for a better flowing muffler.

Jsut my expereinces. Hope they helped.