question about uppipe

[O3 subaru WRX]

ok so, im pretty new at this but...

is it good for a 03 wrx to have just an uppipe with no cat system?
i heard from someone that in the 06+ wrx models that they took out the cat system and just had an uppipe (2.5L). but im not sure if the guys car im looking at is trying to convert to this system with an 03(2.0L).

if additional parts are needed.. downpipe, cat system... let me know, im just trying to figure this out right now

[Micah]

Originally Posted by O3 subaru WRX

ok so, im pretty new at this but...

is it good for a 03 wrx to have just an uppipe with no cat system?
i heard from someone that in the 06+ wrx models that they took out the cat system and just had an uppipe (2.5L). but im not sure if the guys car im looking at is trying to convert to this system with an 03(2.0L).

if additional parts are needed.. downpipe, cat system... let me know, im just trying to figure this out right now

The uppipe in the 2002 through 2005 has a "pre-cat" which is known to restrict exhaust flow prior to the turbo and may also break apart over time sending small bits of material into the turbo. Both of these are bad, and that's why people will either replace the uppipe completely, or "gut" the stock uppipe. Doing so will require you to place a 2.2k ohm resistor (look that up to confirm, but I think that's right) in the stock O2 sensor to avoid a CEL.

It's probably the most popular and commonly performed mod on 2002-2005 WRX.

[TheJ]

+1

Welcome to the club