Im wanting to add HFCats to my IPL to finish off the sound with the Stillen Cat Back. 2 questions for everyone, 1st has anybody else in the ATL area done this and how does it effect your emissions check? I had a 84 RX7 with headers, Racing Beat Exhaust and a HFC from Random Technology. it always passed but just want to be sure. 2nd Q- What is the difference to the normal HFC i have seen discussed on the site and a Resonating HFC? Im guessing the Resonating sounds different. I want a more growl sound like I hear on some of the YouTube vids but not cheezy like a Honda with a trashcan muffler on it.

 

Georgia has the same emissions testing as Texas. You'll be fine as long as your HFC's have a j-bung to install the O2 sensor out of the exhaust steam. Resonated HFC's have a widened section of pipe that cancels out some of the harshness. Fast intentions is the only company that makes them AFAIK.

 

as long as you are retaining cats you will be fine...

 

As long as we are on the subject ... does anyone have experience with HFC's and emissions testing in the "Air Care Colorado" areas? Our test includes visual inspection (including a mirror to verify that the cats are in place, OBD monitoring, and emissions testing on a full dyno).

Thanks,
Greg

 

As long as you have quality high flow cats with the aforementioned J-bung, you won't throw check engine lights. With that, you should have no problem passing a visual inspection or an OBD monitor. If they get the sniffer out, you might want to worry.