Hi All

I am between just getting Fast Intention HFC or replacing the whole exhaust. My buddy is a mechanic and told me that the G37's (I have an 08) have a very open exhaust as is/stock and that the CATs are the bottleneck. He said replacing the CATs is enough and a full exhaust system doesnt do much on performance, rather it is for sound. So the thing here, being that a full exhaust system costs double what the HFC cost and really to gain little to no more than just sound?

Currently I have Injen Cold Air induction and I want to open the air flow. My buddy is a smart guy, but obviously here is the best place to get and take advice. Please let me know your thoughts.

 

It's true that a CBE won't give you power (well nothing noticeable). But HFC is for sound too and only mildly effective performance wise towards the higher RPM's.

For serious power for this car, you need to either SC or TT

 

I say Best setup is true dual CBE with stock intakes..

 

HFCs are the best bang for your buck mod IMHO. An aftermarket CBE is mainly for the sound...despite what manufacturers claim, you're not gonna get much performance gain. The HFCs keep the stock exhaust note, but it's much louder and deeper at low and high RPMs...not as loud as you will get with a CBE (depending on which CBE). HFCs will also give you more noticeable performance gains. I have the FI resonated HFCs...since having them installed the acceleration is much better...especially from a dead start...and the acceleration lag is pretty much gone.

If you're looking for performance gains and a better exhaust note, I'd definitely go with the HFCs first then add the CBE later (if you don't have the means to do both at the same time).

 

I got Ark CBE and berk's HFC's, I got noticable power gain on my IPL. The sound is amazing and was good choice on my part.

 

+1 for the ARK.
I have Stillen HFC's and the ARK Grip Cat Back Exhaust.
Power, Sound and awesome look of the ARK.
Get the ARK Grip CBE, if you can afford it.

 

Is there much of a difference in between brands of HFCs?
Berk, Fast Intentions, Stillen, etc....
And what is the difference in resonated and non-resonated?

 

I ran Gen 3s/Fast Intentions RHFC w CBE and the power was amazing. Very much a night and day difference from stock.

 

i decided to go with HFC for now and probably get Ark exhaust later!

 

When installed with a stock CBE, most HFCs are pretty similar. But, when pairing some with an aftermarket CBE, you will get considerable drone and rasp. From what i've read this is especially true of Berks.

Resonated HFCs do not produce any rasp or drone...you may get some rasp with unresonated HFCs.

I went with the RHFCs from Fast Intentions because with a stock or aftermarket CBE there is no drone or rasp. They are more expensive than some other brands, but you get what you pay for IMHO.

 

dyno 10 whp from stillen hfc. already had stillen cbe too

 

Thank you everyone for the help. I think I am going to go into a group buy here for Fast Intentions Resonated HFC

 

That will be good. You going to do a before and after dyno on this so you know the gains?

 

So I have cold air intake from Injen and I have been told the bottleneck is the exhaust, specifically the CATS. Since I can not afford the whole exhaust system, I am just doing CATs now (Fast Intentions Resonated HFC seem to be the best rated here).

My buddy said the next logical thing to do is get the ECU tuned @ UPREV to recognize the new modds. With the ECU tune you have to pay for a dyno too... that whole process is like $600-700. So long story short, Resonated HFCs, bolt them on myself, and wait until I save up another 600-700 bucks

 

Really? I thought that the IPL already came with a high performance exhaust system. Otherwise how did they increase the HP & TQ without putting in a CAI?