[R99]

Hi all.

Now, I know NOTHING about the technical side of MINI ownership, I even got stuck changing the headlight bulbs!

But, I've been thinking about this for a while.... over the summer I got an aero kit put on the car, and as a result I needed a new exhuast (due to the ONE D's been bent down and hidden behind the standard bumper)

Anyway.... I eventually got a custom back box with a 3" slash tip put on the car by a local PowerFlow agent, for a reasonable £160 (not bad for parts plus three hours labour) The result was good, the new back box has given the car more of a deep grunt, it sounds much nicer than before.

However at the time the guy who went through the options with me mentioned a straight through pipe, with no cat. He told me that this would reduce 'back pressure' which is apparantly something Turbos hate, he also said that as its a diesel no cat is required to pass MOT's etc. He said that I would probably see performance gains too.

Now at the time I decided to just go with the back box, mainly for cosmetic reasons and as an easy soloution to my exhuast problem. Plus my funds were low due to the purchase of the aero kit itself!

My question really is.... would it be worth considering getting a decat pipe? My concerns with tuning a diesel are that its going to smoke alot when I boot it. If thats the case I'd rather not bother. Does anyone know what if any power gains would be possible, also would it sound any good?

Any opinions? I know there are some knowledgeable people on here!

Regards,

James.

[Ant FR]

Ok, i have mentioned this on a few posts before.

My old car was a very nice tuned 200bhp Diesel, the method you are talking about is what the diesel boys call a mufflerectomy. First off on a diesel there is no emissions test, so there is no real requirement at prersent to have a cat, in fact they end up so coated after a few years there ineffective anyway. So yes you can bin that straight off. There is also a need on diesels to have the back pressure as low as possible and your guy is right in that you can lose the boxes too. it does increase in sound, but its usually a nice deep growl under accelration. The only downside is it could be a bit droaney inside the car at speed. All cars are different. You should also be aware that the Turbo itself actually acts as a silencer anyway

It should not smoke anymore as the exhaust does not reduce the smoke on a diesel ( well of that era anyway) the only reason diesel will usually smoke more is due to being remapped where the usuall stance is chuck in as much fuel as possible, the smoke is the unused dirty fuel coming out the system. Or alternatively if you are runnng on Cherryade which i am sure you would'nt do, even though it is only 40p a litre as apposed to 99p for normal......

Go on try the mufflerectomy. If you have a search on SEAT Cupra.net under mufflerectomy you will get some more info

[R99]

Thanks for that info mate, very helpfull.

I know it will depend on the car, but roughly how much of a gain would I see from doing a mod like this? Bearing in mind that my car has no performance mods on it currently and the engine is stock. The only non OEM item is the back box mentioned in the first post.

Many thanks.

[Ant FR]

you will definately feel it in the pick up, should rev a lot more freely and should also feel smoother. Whether you gain any real BHp is an unkown, maybe you will maybe you won't, but the sound will defo change, and they sound quite deep. Think Le Mans Audi TDi,