I'm pondering getting a HFC for my G37 Sedan and i want to know which one out of all thats available for the G37 Sedan (Stillen, Berk, AAM, Fast Intentions) produces the least smell.

I'm been told and read about people getting a weird smell after changing the stock cats to HFC so i'm just curious about this and also want to know which produces the most gain....thanks.

 

I never heard of HFC's producing a smell. They are still cats with just a less restrictive core. I've heard of test pipes producing a smell, but not hfc's. I might be wrong, but that's always been my impression.

 

Don't forget Kinetix.

 

It's more like, the more the smell, the more the HP lol

 

It seems like there is a little more smell with HFCs, but you will not be smelling it in the car, it really won't be noticeable. You only get the strong smell with test pipes.

 

Smell comes with all HFC's. Kinda hard to gauge the amount of smell that "HFC X" makes compared to "HFC Y".

All HFC average about a 10-12 hp gain.

 

The smell that leaks out is the smell of "un-catalyzed" NOx gasses. OEM catalytic converter catalyze the **** out of them, yes it's cleaner and doesn't make a smell, but it's also restrictive due to the high cell concentration. High flow cats are a little less restrictive meaning they lead to a free'er flow hence the 10whp gains however the smell is very minimal. Test pipes have no catalytic converters. Just a bunch of free flowing pipes. Those yield the most whp

 

Thanks for all the responses guys. Of the following Stillen, Berk, AAM, Fast Intentions, Kinetix which one would you guys recommend? I notices that a lot of forum members have Berk, is that the best out of the group?

 

They are not all the same. Different cell counts, some are metallic, the Kinetix are ceramic. Also, don't forget about the CEL light.

 

Yeah, the infamous CEL light. I read a thread earlier about the Berk and the CEL light and majority of the users didn't get the CEL light at all or had it resolved. I haven't seen much more about the other HFC.

SilverBullet, have you received a CEL light with your Kinetix?

 

The smell with the high flows is very minimal. The only time I smell it in the cabin (I always have my windows down) is when I get on it and come to a complete stop.

 

So far, no light. But Kinetix also advertises no CEL light. I also added non-foulers just to help.

 

What's the difference between a metallic HFC and a ceramic HFC? I'm thinking about picking one you but don't know should I go with Berk or Kinetix.

 

Does anyone know what type of brand Magnaflow generally uses in their catted x-pipes (for other cars). I had their cars from those pipes on all my stangs and they made awesome power, sounded great and didn't smell. If I could buy something similar in design for the G that would be great.

 

Whats are non foulers?