De-Cat opinions plz
If you remove all of the cats, you will need to swap one back in at MOT time, to pass. The centre (most rear cat) is the easiest to swap in and this takes about 10 minutes to do.
There have been several full de-cat 01/02 WRXs that have been on the rollers. A full decat will achieve 255-260bhp. A turbo back de-cat (leaving the up pipe cat remaining) will achieve 245-255bhp and will still pass an emission test.
Apart from the extra power, a full de-cat will get on boost much quicker than the standard exhaust and the throttle response will be much better.
There have been several full de-cat 01/02 WRXs that have been on the rollers. A full decat will achieve 255-260bhp. A turbo back de-cat (leaving the up pipe cat remaining) will achieve 245-255bhp and will still pass an emission test.
Apart from the extra power, a full de-cat will get on boost much quicker than the standard exhaust and the throttle response will be much better.
Joined: Apr 2002
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From: The hell where youth and laughter go
depends...
If you have a Full de-cat, it will fail the MOT. But you can remove the mid-section cat with no bother (that's what the PPP mod does), it's also the easiest one to remove.
The biggest power benefit is by removing all the CATs (obviously) as the restriction in the exhaust system is removed. Especially the downpipe CAT IMHO.
Expect less turbo lag, more overall power, and more power off-boost.
If you have a Full de-cat, it will fail the MOT. But you can remove the mid-section cat with no bother (that's what the PPP mod does), it's also the easiest one to remove.
The biggest power benefit is by removing all the CATs (obviously) as the restriction in the exhaust system is removed. Especially the downpipe CAT IMHO.
Expect less turbo lag, more overall power, and more power off-boost.

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