View Full Version : Stock downpipe, cat delete + 3" catback exhaust

12-05-2011, 02:34 AM
Has anyone tried removing the stuff in the cat, retaining the stock downpipe and putting the cat back in with a 3" catback exhaust? What kind of EGTs do you get on those. The noise and vibration from the 3" downpipe is getting to be bothersome. Maybe I'm getting old lol.

12-05-2011, 11:39 AM
Tony, im not sure if I put those exact dyno graphs up in the other post regarding 3" systems but I do have the data in the dyno still. I will try and dig it out tomorrow for you.

Basically we found the difference between std cat, 200cel metal substrate hiflow and no cat was all of about 2kw between them, less than 10deg temp difference at the turbine outlet and a huge .06psi backpressure difference.

Thats about the only reason I refuse to sell turbo back systems on the D40, its just robbing the customer for nothing.

23-05-2011, 12:12 PM
What about D22 2.5??