sMoggY06

Evening folks,

Im tryin to get a bit more power from my WRX. It's already got cat-back exhuast but wanna do the full system whilst still retaining one of the cats.

now I'm not 100% sure aout the right way to go about this as I've been told the Hawks exhaust system differs from the Blobeyes.

AFAIK there is no up-pipe cat anymore... And I've been told that the downpipe has 2cats in it...and then theres also one in the mid section?? Is this correct????

If this is the case could I replace the Downpipe with a Decat downpipe and then this would take them 2 cats out with the one in the mid section remaining??? Is this cat alone enough to pass an MOT?

That seems like the easiest way to do it?

Does anyone know how much difference this would make compared to having a proper Sports Cat in the downpipe and decat mid section once remapped.....would it be a big hit?? Coz if its likely only a few BHP...then I cant justify spending the extra £400 or so for a Sports cat and decat mid section.

Also, does decattin the Downpipe throw a CEL light? IIRC it did in my 04WRX?

Any info would be appreciated

Cheers

Deano.

BlueBugEye

iTrader: (12)

Best Cat to keep for MOT would be the Downpipe Cat - I have a sports catted centre section and it will pass but only when v hot. I have another MOT today and I'm not convinced it will get through...!

BrownPantsRacing

iTrader: (6)

Hawkeye’s don’t have a cat in the up pipe so that’s easy. Do have one in downpipe & second after that. Have a 4 part system with joint between the downpipe & cat pipe. On mine I change dthe whole system for a 3 part system with only 1 sports cat in the downpipe. Passes MOT fine. You will need a re-map if you change the exhaust though.

sMoggY06

Cheers for the info lads.

How much did the sports cat cost mate??

Brownpants:

So....

If I get a decat downpipe, will this take out 2 of the cats and only keep one remaining in the mid section, is this enough to pass an MOT? And how much of a hit would i Take on performance vs Sports cat downpipe and decat mid once remapped?

Cheers,

Dean.

BrownPantsRacing

iTrader: (6)

Go on the cobra website, that's where I got mine from, very helpful indeed. The downpipe will replace both of your cats with a single sports cat in 1 new longer downpipe section.

Sports cats have to get hot to work and pass emissions so the closer to the turbo the better. If your just going to get rid of one then keep the one closest to the turbo. Full sports cat downpipe definately better option. Mine from cobra was only £225 new.

Good luck. Andy

sMoggY06

cheers for the reply.

So this would replace the mid section Cat aswell??

As in if I bought this and had it fitted, thats all i would need??

BrownPantsRacing

iTrader: (6)

The new downpipe replaces both the standard short cat downpipe and the seperate cat after it. Effectively making it a 3 piece system. New pipe goes between turbo and exhaust centre pipe.

Wagon Gaz

iTrader: (18)

Mate as far as I know there is no cat in the center section. Cat in the downpipe, followed by another cat, then center section with resonator and then your back box. Removing the second cat releases some power be carefull though as the 2nd decat pipe on the Hawkeye is slightly longer than the Blob/Bug.

BrownPantsRacing

iTrader: (6)

Correct. Centre pipe only de-resonator pipe. System goes, rear box, centre de-resonator pipe, cat pipe, cat downpipe, turbo. Last two pipes I.e. cat downpipe and cat pipe can be replaced with the one new sports cat downpipe leaving centre pipe and rear box.

Also centre pipe and rear box are same length on all newage 01-07.

sMoggY06

Cheers for clearing that up lads, had a bit of confusion there!

SOOOOOOOOO.......one last thing ....

I'm right in thinking then, if the car has a cat back exhuast this will have taken out the centre pipe with resonator box?

uk300scoob

iTrader: (24)

07 hawkeye went through mot with a full system de-catted and up-pipe, uel headers also emissions all passed

BrownPantsRacing

iTrader: (6)

Correct. It will now have an aftermarket resonated or de-resonated centre pipe.