Tune will increase the performance and make your car run great!! Maybe sometime soon Motordyne will come out with a pleneum spacer or Mrev 3 or something for you guys to make your motor's awesome as well. If you don't plan on doing anything else then I would just go get a tune then. It will be worth it in performance gains in the engine plus the engine will be running at its prime at all times.

 

the tune is the most thing you'll feel other than going FI. trust me, this is no theoretical hp stuff.

 

Anyone else have thoughts? I'll probably go forward with it and get the $500 upRev package

 

wow! You talked me into getting HFC now if it really adds that much HP! It better gain that much for a 2nd Gen sedan for me

 

I just think I'm jealous

 

Get a tune if you don't plan to do any more bolt ons.

Cats are the most restrictive part of the exhaust and you can expect 5-10 whp from the cats alone. With a tune you could see increases of as much as 15 whp is my guess.

 

on a g37:

http://myg37.com/forums/intake-and-e...no-tested.html

 

Don't expect noticeable change from cats alone. I still think a full cat-back is required if you want bang for the buck and noticeable gains.
I would only worry about drone on certain systems.
The Fast Intentions system has no drone, even on the highway.

 

Those dynos on g37 showed a measurable difference with just cats so why shouldn't I expect to notice it? If anything, I'd think I shouldn't expect to notice the difference from just cats to cats w/ a cat-back. That's gonna net all of 4-5 more whp? 5hp isn't "noticeable" until you're looking at .1's or .01's in the quarter or on the track.