I did some searching but it seems everything i found was the HFC on an aftermarket exhaust. Has anybody done this with the OEM ? In another
thread awhle back someone mentioned that gas milage improved quite
a bit. How about the sound ? Thanks to all

 

good question, im curious as well bc i was thinking about running the berk header + berk hfc on an oem exhaust too..

* for an answer*

 

I have a Berk's hi flow cat and I'm happy with it. I still have OEM header and OEM exhaust pipe. Unless I could get good gain out of a after market header, I'll stay stock. As for the exhaust, I'll leave it alone for now because I want it to stay quiet.

 

When I installed my Berk Tp I noticed a little throttle response. Exhaust sounds a little raspier though. Oh, and it made the vtec screams.

 

sound clip of my S with berk hfc and invidia v3

http://www.youtube.com/watch?v=Ox3vDJK37A4

 

make some sound clips. i would love to hear them.

 

i have the megan header, berk hfc, and oem exhaust. the header made the vtec a lot louder, thinner walls i guess, my car is timid 'til vtec and then it get's loud (plus the prm intake), but the oem exhaust tones it down to prevent "fart can" obnoxious noise levels...