Hello G37 guru's,

Just a bit of history on my vehicle, i drive a 2008 G37 Coupe 5AT with Cobb intake tubes, HKS drop in filters, and fujitsubo cat back exhaust. Recently, I finally got around to installing my Kinetix HFC that's been sitting in my garage for almost a full year. The vehicle use to sound perfect to my ears! There was no rasp, it was quieter than stock with a nice deep low tone. However, after installing the HFC, the sound is now slightly louder (expected), but there's a tonne of rasp from mid-high rpms; especially when the car is changing gears or under hard acceleration. Also, when the engine is cold, I can hear the valves ticking. When i accelerate slowly, it sounds kinda like a go-kart, but once it picks up speed (0-5mph) or when it warms up, it goes away.

Does anyone on this forum have the same exhaust combo as i do and experience the same problem? I know it's an odd combo since not many people go with Fujitsubo.

The funny thing is I have 2 other friends who are using the Kinetix HFC on their G sedans, and none of them have this problem.

Am i **** out of luck?? maybe a leak in the gaskets?

The HFC currently has less than 1000km's on it. Should I continue to wait and see if the sound changes? or should I just sell it and go with another HFC?

But putting this all aside, the Kinetix HFC makes pretty good power, i'm actually quite impressed.

Thanks

 

I'm not sure of your particular combo, but after I ordered Fast Intentions RHFCs, the rasp from my Stillen exhaust was reduced.

 

Plain and simply, the Kinetix HFC are absolute garbage. That is your problem. Many HFC will add some rasp if they are not resonated, that's the nature of them. But Kinetix is the worst possible.

I don't have them. In fact I took off my HFC altogether (I had Berk) and am very happy with the result. But I have heard the FI resonated ones on friends G's and they are much better sounding.

 

why weren't you happy with the Berk one's? I hate the sound that the Kinetix produce, but I love the power.....maybe i should look into buying the FI HFC's....

 

The Berk's did definitely add some HP. However, it was higher up in the RPM range and also it was at the expense of adding some amount of rasp and deceleration hiss to any exhaust. A bit of low e3nd torque was sacrificed as well. The product itself was very well made and the service I received form them was top notch. Nothing bad to say about it other than it wasn't what I wanted.

 

yea, i just bought the FI RHFC, hopefully it'll reduce my rasp...i don't mind the hiss so much, it's the rasp that really bothers me!

 

From my experience: Stock exhaust + only MeganRacing RTP = RASP from 4000 rpm.