Would it offer any significant flow gains? I want to keep a cat in the DP and I'd like to stay with the quality fit and finish of OEM. I'm not trying to build a 300hp car here, it's my daily driver and auto-x car so small improvements that actually help with power and driveability without any loss in reliability are all i'm looking for. I imagine the STi DP would have to flow better than the WRX piece but I'm just guessing. Anyone know? Also would it flow enough for cobb stage 2 mapping?

 

As far as I know they're the same DP.

 

yes, they are the same downpipes, with slightly different mounting brackets....

I have a gutted sti downpipe on my wrx, and i dont think it flows well enough for a cobb stage 2 map still.... Best bet is just get aftermarket.

 

Dont bother, its got the same 2 cats. If you got if for free, then gutted it....that would be better than stock