Does anybody have any data on performance gains by adding a cat back exhaust ? If the brand matters I'm talking about fast intentions.

 

With the OEM cats expect gains of 15hp or less, replacing w/ HFCs or TPs will gain another 10-15 give or take. Typically the gains will be at the uppermost RPM range w/ possible loss of low-end torque.

 

The G's engine is pretty highly tuned as it sits. It's expensive to get much more hp out of it without going forced induction. But for a full CBE the number that Brad described are what I've read as well. I have a full Ark grip CBE and r2c intakes and honestly don't feel a difference. Probably bc I have a 7at.

 

So any way to get the lower end torque back? I just put the fi cats and cbe. Will take it out on the highway later today but first impression is the launch is not as quick. Not sure if it is in my head or just need break in. Just drove it a mile or so. Tonight I'll take it on the highway to see if it feels different. The sound is a little.louder than I expected. I think i feel some vibration. Will feel it out and then maybe take it back for them to see if I could get rid of vibration. Most definitely a rumble while getting to 3000 rpm.