if i get a DP/RP combo and put a High flow cat in the RP, will it be just the same as just getting a race pipe, because the 1st cat is a high flow one already..
emmissions arent an issue, they dont check them down here.. i just dont want to look like a diesel truck going down the road if a bit of oil leaks past the rear turboseal
if it start smoking replace turbo during warranty or put oil catch can.... but your car is 08 I didnt hear tha any 08 ms3 had problem with turbo seals you shuld be good