wrx_improve
Scooby Regular
Joined: May 2000
Posts: 10,371
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From: MY00,MY01,RX-8, Alfa 147 & Focus ST :-)
Just to expand a little..
The new WRX has three catalytic converters (in the EEC anyway) - one in the 'up pipe' from the turbo, one in the 'downpipe' of the exhaust and one in the mide section.
Obviously taking all of these out does improve the flow of gases. Combined with a decent air filter, you should be looking at improvement of roughly 30bhp and 30lbs torque. Figures will vary from car to car and the environment that you're in (i.e. Israel is a little warmer than the UK, so power gains maybe different).
Many people change the downpipe and centre sections - leaving one catalyst in the up pipe - that's what I've done. The Up pipe cat is considered the most restrictive but it costs more and you have to consider whether you want to run the car completely cat-free.
I would also consider installing a boost gauge - preferably before you make serious changes / modifications - so that you know what boost you are generating and avoid any potential problems.
After decatting you are looking at ECU modifications. You could also consider a front mounted intercooler, stainless steel headers for the manifold. Then it will be time to look at suspension, brakes etc the list goes on.
On other thing to look at is a Dawes Device - a manual boost controller - properly setup, this will give decent improvements - but do your homework before fitting. Have a look at J W Racing for more details or do a search - there are loads of threads on it.
Cheers
Chris
[Edited by Chris L - 12/27/2002 10:03:12 PM]
The new WRX has three catalytic converters (in the EEC anyway) - one in the 'up pipe' from the turbo, one in the 'downpipe' of the exhaust and one in the mide section.
Obviously taking all of these out does improve the flow of gases. Combined with a decent air filter, you should be looking at improvement of roughly 30bhp and 30lbs torque. Figures will vary from car to car and the environment that you're in (i.e. Israel is a little warmer than the UK, so power gains maybe different).
Many people change the downpipe and centre sections - leaving one catalyst in the up pipe - that's what I've done. The Up pipe cat is considered the most restrictive but it costs more and you have to consider whether you want to run the car completely cat-free.
I would also consider installing a boost gauge - preferably before you make serious changes / modifications - so that you know what boost you are generating and avoid any potential problems.
After decatting you are looking at ECU modifications. You could also consider a front mounted intercooler, stainless steel headers for the manifold. Then it will be time to look at suspension, brakes etc the list goes on.

On other thing to look at is a Dawes Device - a manual boost controller - properly setup, this will give decent improvements - but do your homework before fitting. Have a look at J W Racing for more details or do a search - there are loads of threads on it.
Cheers
Chris
[Edited by Chris L - 12/27/2002 10:03:12 PM]



