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Aftermarket DP with Stock catback Help

2K views 3 replies 4 participants last post by  newtothegame 
#1 ·
I want to know if anyone has an aftermarket dp with a stock catback. I have read that this is considered stage 2 but are the power gains as noticeable as a full turbo back. I am thinking about going catless dp for now as there is still a cat in the mid pipe and a resonator.

Has anyone done this? If so how much louder is the exhaust? Sounds clips maybe? Thanks for any help!
 
#2 ·
There shouldn't be a cat in the midpipe - there should be two cats in the downpipe and one in the up pipe if you have an 02-05 WRX (06+ WRXs and all STi's come from the factory with catless up pipes). True, you'd still be considered stage 2 with an aftermarket downpipe, stage 2 ecu reflash, and stock cat back, but you'd see slightly higher gains with an aftermarket cat back since many of those utilize 3" piping and the stock cat back pipe is only about 2.25" in diameter.
 
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