I'm stage 1 on COBB. When I upgrade to Stage 2 shall I run a catless or catted DP? I will buy a shorty. I have a catless midpipe now. I wonder If i need a bit of back pressure to keep the torque. Or Just go catless......
my exhaust is catted and i'm putting down around 400whp on SOG's dynapak... i know of another who is running a catted exhaust with meth injection and is running 500whp... i doubt a high flow cat causes much restriction to the flow... some other things to consider: 1) catless tends to be a little louder than catted (with other mods unchanged) 2) if you ever intend to run leaded fuel, go catless 3) catless exhausts smell worse than catted exhausts 4) catless exhausts are more likely to shoot flames when they pop... if ur into that kinda thing
Your car won't pass inspections catless. That doesn't matter in good ole' south carolina though. If you can afford the extra money, get a high flow, like milo said, its not much different than catless (maybe 5hp at most).
i know georgia only requires OBDII testing for emmissions... so if you have no CEL, you should pass fine... this can be taken care with appropriate tuning now if the inspector decides to go for a visual inspection, u will be in trouble if you have no cats... however, i dunno if those of us with aftermarket cats are any better off during visual inspections because i believe that by law, we are not allowed to tamper with factory emission control systems....
Are you serious on that we are not allowed to tamper with factory emission control systems.... ? Can someone find the fine print on that. It would bite if that was true. We would have to start looking for "tuner" friendly emissions places then.
If the law holds no effect on you, the only bottom-line down side is the fumes filling your car in traffic. That can't be good for you...
i don't know how strictly it is enforced... but i remember when i first had my exhaust installed on my WRX back in 03, i took it to a muffler shop... he flat out told me that if he had to remove a cat, he wouldn't do it... there's a fine for me if i'm driving around catless but his fine would be HUGE for removing it... if you get it done at performance shops, i guess the waiver you sign takes away their responsibility :dunno
i was georgia state certified to do emmissions inspections for 3 years and part of the test is a visual of the cat, even on obdII cars. the thing is that like alex said the shop mistook his resonator for a cat. most people dont know about suby's. you could just point out your manifold coming off your heads with the heatsheilds and say the cat is behind the heatsheilds and they would beleive you. last time i took my for inspection the kid performing the test the was so interested about my car he didnt even think about looking for the cat. there are ways around it