papascooby

as well as maintaining my warranty?

Also, would a decat affect the warranty? Are they legal? Someone at work mentioned something about you not being allowed to do it on newish cars.

Could I expect 250BHP? What would the torque increase be?

mgg

Im new here, so i could embarass myself if what i say is wrong, but i dont think it is as ive done some serious research as im looking at buying an Impreza pretty soon.

ITG panel filters are commonly used, you could expect to gain about 2 to 4 bhp by fitting on of these.

Decat is legal on the road but you would have to change it back to standard for servicing or mot, but mot isnt applicable for you. This would increase the flow of gas and increase your engine power, but i have no idea of what gains you could expect.

As for a pro drive back box, this would not affect your warranty, as the exhaust sytem isnt covered on warranty, as its classed as wear and tear products. Gains in power from a back box wouldnt be anything special, a few bhp. But if you replaced the whole exhaust sytem, you would get much bigger power gains.

Hope this helps.

Think thats ok, connsidering im new here.

papascooby

If you read the post comparing the two filters in this section, you'll see that the Sti filter seems to be better thean the ITG one.

keevster

iTrader: (1)

Hi, I have an MY04 WRX and have recently carried out full decat magnex and JW panel filter. Had it on the rollers couple of weeks ago and i gained 35bhp and an extra 16lbs/ft of torque. pretty impressive.

Paul

scooby L

Just be aware, de-catting your car can increase the chance of DET (lean fuel/air mixture), most people have the car Re-mapped to gain maximum benefit from the de-cat while ensuring safe fueling.

the STI filter seams to be the peoples choice.. I've just swapped from a green filter to the dry STI panel and have noticed a difference, but this filter is a Jap part.. not UK, so warranty could be an issue.

papascooby

So, I guess I just need to check with Subaru about the warranty / panel issue and forget the decat unless I get an ECU remap?

and from the sounds of it i might make 250bhp without the decat if I'm lucky?

Fangoria

iTrader: (1)

Why dont you just go for an ecutek?

There is no way that a dealer would be able to tell that you have this done

Re other comments. I'm pretty sure that a decat is ILLEGAL on the road as the police can do spot checks and have the ability to fine you for not having one - pretty rare though.. that said I wouldnt really hesitate to decat mine - I'm gonna decat my new wrx and I've had a decatted sti5 now for nearly 5 years (MOT's included with your nice friendly MOT testing station)

250bhp is dependent on whose rollers you go on -I'd be pretty sceptical of 35bhp from the best system out there.....then again if the gain was at Well Lane- maybe - but at G force or Powerstation you've got more chance of winning the jackpot on the Lottery than getting those sort of gains!

papascooby

what's an ecutek?

<Edit>

found out

i think subaru could tell pretty easily

i think i'll just stick with the sti panel filter and prodrive backbox and hope I notice the difference

Chris L

You don't have to fully decat. I've run an MY01 WRX for nearly 3 years with a partial decat system. I've replaced the downpipe, centre and back box, but kept the up pipe with the smaller cat in it. There is a noticable improvement in performance and it sounds great. I've run this for more than 50K miles with no remap and the car has performed faultlessly.

I also use an STI panel filter - highly recommended. I know they aren't strictly available in the UK, but I think Subaru UK would have a pretty tough time saying that an official Subaru part had affected the car!

Chris