So my RX-8 with Greddy SP2 cat back shoots fireballs while on the race track.

Is this really bad for the engine or cat? I recently had a cat replaced under warranty and I was wondering if the flaming exhaust could be a problem.

I've gone back to stock for now and I might sell the exhaust and keep it stock but I really miss the exhaust sound...

well, its not bad for the engine, but its definitly saying something about your cat, got nothing to do with your greddy exhaust though, it just happens with the rx8 I guess

Not bad per se...but most people get "teh flame job" after removing the cat...

Dont think it's really doing much to hurt your cat or anything...but dont quote me on that...

I'm not the authority on this but the flame is charateristic to this car due to the unspent fuel in the exhaust. I think it's a pretty normal phenomena for this car and from what I've read elsewhere is harmless and adds a "cool" factor to the car. The OEM cat prevents it from happening. I know that most people experience it when they are using a straight pipe instead of a cat. I would suggest that there might be a problem with the cat, because normally, the cat would prevent the flame from happening.

If you've ever revved your engine and you hear that "popping" sound out of your exhaust, that's the unspent fuel. Without the cat you would get a flame.

I get it like 99.9% of the time when I'm driving really aggressively without a cat. I've actually seen incidents where flames shoot out on other 8's even with a Cat on.

^ listen to this guy he knows what he's talking about

mostly cus the 2 burnt marks on my front grill he left