Hey guys,
Im thinking of buying a decat downpipe and decat mid section for my 2005 wrx. i was just wondering if i would need to get the car remaped after fitting these or will it be ok as it is?
Do you think the increased power will be noticable?

cheers guys.

 

hi mate, decat mid section wont require a re map but if you decat the downpipe then you will need too. your running the risk of over boosting. you wont notice hardly any power increase with out remapping
hope this helps

 

You will get a mixed response to the this question.

The effects of the decat put simply is reduce back pressure on the turbine allowing it to spool quicker and potentially create more boost, you will therefore need more fuel in the mix. WRX tend to run a little rich anyway so you may well be ok. Other things to bear in mind is that you may get overboost etc etc

I tend to ere on the side of caution and suggest that you get the car remapped. If anything you will derive far more benefit from the mods. Don't forget the cat in the up-pipe as well which is definitely worth getting shot of if you doing the rest.

 

you should have a remap after getting a full de-cat,the fueling is going to be way of.but up side is if your car was standard before you could be looking at 280 bhp in a healthy motor.

 

I would have a remap after a de cat. It will get the best out of your car and the modification. The power increase from the de cat alone will be noticeable, but a re map will literally blow you away. I cant put into words the difference, all I can say is it will make you smile . Expensive, but worth every penny.

 

thanks guys for the help. how many cat have i got then? its a wrx300 05. had ppp as standard so the exhaust is upgraded but im not sure excactly how much of it. i mean do they remove a cat as part of the ppp?
would it be better if i just replace the one?
if i changed the one, how do i stand with MOTs if theres still a one cat on there?

sorry guys i know i just asked a million questions but im just trying to get my head around it before i waste money on something i dont need.

 

i think im right in saying ull have one in the up pipe and with the ppp package you should have a sports cat downpipe therefore you would be ok for mot time,aswell as benifiting from a remap without having to decat

 

I think they whip the centre cat out with the PPP on the WRX. That leaves you with 2 of the pesky fekers.

If you are concerned about MOTs etc, then get a 2nd hand Prodrive sports cat downpipe, you can usually pick them up for about £200 on ebay. I ran one on my Impreza and it sailed through the MOT.

 

Sports cat only came with the STi PPP package.....

 

ahh ok,didnt know that

 

you will have standard uppipe and downpipe cats fitted still plus the prodrive decat centre.

get a first decat pipe and a decat uppipe you will also need a 2.2k resistor to put in the egt sensor plug.

this is the one i used cost a whole 33 pence.
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keep an eye out on ebay for a standard centre cat and come mot time just swap it with the prodrive decat section,a lot easier than doing the downpipe one.

a newage will pass with just the centre cat mine flew through no probs.