madey

Is there a up pipe with a cat on a 04wrx? If so, is it a worthwhile job changing it? Cheers, Mick.

Butty

iTrader: (2)

Yes and yes, but do the work at the same time as other work as it is a time consuming job and really needs a remap to get the most out of doing it.
Nick

madey

Thanks for that, the car is fitted with a PPP so I intend to fit a decat downpipe (pick the car up tomorrow) so I could have both jobs at the same time. Mick.

Welloilbeefhooked

iTrader: (3)

Change it for a classic up pipe that doesn't have a cat.

If I was doing all that work I would get the headers ported along with a little bit of work to the new up pipe at the same time.

I think you may need to deal with the CEL that arises from the removal of that cat.

Wayne.

34srm

its not gonna need remapping

Welloilbeefhooked

iTrader: (3)

Thats fine until you read about him having a decat downpipe fitted. Having it mapped will set things right and you will only know if it needs mapping by checking the afr's and for det.

It probably won't NEED mapping, but its adviseable.

Butty

iTrader: (2)

Then that's his risk.
A CEL will appear without a remap as the EGT sensor will not be functioning. This can be tricked with a 2.2 kOhm resistor.
The decat will also raise a CEL for the rear oxygen sensor. This is a mechanical or electronic fix (or a remap).

Nick