I'm trying to decide what DP and cat options I should go with for my 05 MR. I have a 3" Ti catback but I've read that the 3" dp can cause flow issues and affect driveability. I'm thinking of going with the JIC dp and a high flow cat. What gains have people seen/felt with the dp upgrade without a flash? My only mods are K&N dropin, MBC and the catback.

Search but couldn't find this specific info, any input is appreciated

Thanks,
-Dave
05 WW MR
04 FXT
98 A4

 

a 3" downpipe is not going to cause flow issues. You will gain power and a little boost, with a slightly higher spike.

I think you could expect anywhere from 5-10 from the downpipe and anywhere between 10-20 on the cat.