Aero

The only mods I have are a Magnex Midsection with resonator and a scooby sport back box.

MY94 WRX type RA listed by Subaru at 240ps
so I took that to mean 235bhp, took off another 5bhp for running 97RON and then some more just because she's an old bird. So was expecting 225bhp (bit conservative i guess)
I wasn't expecting (much) of a power gain from the mods, more driveability and better sound, but a rolling road indicated 246bhp.
Down to the zorst?
I don't know, but I like it.

scoobysnacks

So it'll pass the MOT like that then - no probs?

scoobysnacks

I've got a standard 98 WRX (43000 miles) with Pipercross induction kit. Will fitting the above exhaust bits give more power (how much?), better sound and still allow me to pass my MOT in March (if I leave the downpipe standard)?

Thanks all.

Chris L

Scoobysnacks.

I run a Magnex backbox and decat centre. The engine is smoother, sounds a lot better and there is some increase in power. I haven't any figures though. To get a real improvement I suspect you would need to do the downpipe as well.

As regards MOT - you should pass with just the main cat in place (in the downpipe). It's a good idea to make sure that the car and cat are warmed up and do the emission test first. There have been cases of people passing the MOT with just the smaller centre section cat in place - but you may need a friendly tester to make absolutely sure of this

Chris

scoobysnacks

Thanks for that reply. I'd read similar posts about the MOT thing but wasn't too clear if it was an almost certain pass with only the downpipe cat in place ('should' sounds a bit risky) - is it? Have you got a de-cat down pipe as well? I know it's a good way to increase power but how much hassle is it to swap back just for the MOT? I'd probably get a garage to do it, but wouldn't want to fork out too much for labour charges.

Chris L

Scoobysnacks

I don't run a de-cat downpipe as there are issues with insurance. Running without cats on an MY98 would be illegal and surely you would therefore invalidate your insurance? Nobody seems to have explained this in adequate detail. You could speak to Rum, as an insurance guy, he could proably explain everything.

I honestly don't think you would have a problem with passing the emissions test with only the main downpipe cat. The secondary cat is only there to meet the ultra strict european noise and emission regulations (as I have been informed by several people).

Chris

ptholt

Thats the first i've heard that its illegal chris.

My take was cars post (i think it was96 ish) had to have a cat as standard from factory,
but there are no laws as such governing removal afterwards afaik.

btw where did you buy such a fine centre section from



[This message has been edited by ptholt (edited 17 November 2000).]

Jay m A

iTrader: (2)

Mr snacks

I'd just like to add that I think your car doesn't have a centre cat anyway! As Chris has said the EU cars only have the 2nd cat, the box in your centre section is just a silencer.

But I could be wrong!

Justin

MTR

Chris L,
Interesting point, about the potential illegality of running a car which will not pass an MOT (on emisions).
I suppose the insurance company, as well as the police could make things rather unpleasant if they wished.

If you had 4 bald tyres when you crashed, the Police would definately nick you, and presumably as the car is clearly not in a roadworthy condition, in that it WOULD fail an MOT, perhaps that could invalidate your insurance, given that you couldn't claim that you couldn't see the tyres were bald before you drove the car, had you bothered to look.

With emissions, however, given that all petrol engined cars built post August 1992 have to have a catalyst to pass the MOT, would the insurance companies expect car owners to be aware of such legislation?

I suppose it may well be like many other regulations, that ignorance of the law is no defence, and you could still be held acountable, even if you claimed that the car was like that when you bought it.

I still have my std downpipe on, primarily to avoid any warranty problems, as my dealer didn't mind me swapping the mid section and back box but was not keen on me swaping my downpipe.

Cheers MTR

scoobysnacks

If my car doesn't have a centre cat, is there much to be gained by replacing the centre section with a Magnex straight through pipe, in terms of power?

MTR

Scoobysnacks,
I think it is just the STi V and presumably STi VI that do not have cats in the centre pipe. They all have a box in the pipe which looks like a cat, but on the models I've mentione are a straight through silencer.
I cannot speak for the power gains on a WRX, but on my MY99, I fitted a Magnex de cat pipe with resonatot box, and there was very little difference. So much so that after running with it on for a while, I swapped the std pipe back to see if I could feel any change. I could, just, and so then fitted the Magnex back on.
Your car produces more power as std than mine, and may be more sensitive to exhaust improvements. Your std exhaust may be working closer to the maximum requirements of your engine, and therfore an freerer flowing, bigger bore sytem may rlease more power.

Do a search to try and establish about the cat fittment situation.

Cheers MTR

Chris L

Does seem to be a bit of a grey issue this. In theory any post '92 car should have a cat to meet emission regulations - therefore if you car doesn't have one - technically the car cannot be considered road legal. Can't help thinking it's one of those things that an insurance company could use against you if they were being really picky (where's Rum when you need him )

Pete - damn fine investment that de-cat centre. Sounds even better now.

Cheers

Chris

[This message has been edited by Chris L (edited 18 November 2000).]