I used to have a 03 coupe with Borla exhaust and Crawford HFC's, but I sold it before it was time for my first smog check. Now i have a 07 sedan with a Stillen exhaust and wanted to get some HFC's but was wondering when its time for smog am I going to have any problems?

 

I believe the Stillen HFCs will pass smog but if they do a visual you're screwed! Be patient, shortly Magnaflow will have there HFCs on the market
that will carry a CARB number making them smog legal in ALL states. I've
know about this for several months, company's sure take their sweet time!
Gary

 

^niceeeee

FI hfc arent legal right?

 

Dunno for sure, but they are listed as "For off-road use only"