Removing a Cat

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Dave Bamber
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Removing a Cat

Post by Dave Bamber »

Does anybody know if you remove a Cat from a vehicle in the search for a bit more performance, are you breaking any laws?<img src=icon_smile_wink.gif border=0 align=middle>
Dave Burns
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Post by Dave Burns »

The cat plays a large part in reducing harmfull exhaust emissions so removing it will more than likely cause the vehicle to fail the m.o.t emissions test, if the vehicle you are using on public roads can't comply with emission laws you are then breaking the law, any tester worth his or her salt will fail a vehicle designed to be used with a cat turning up without one, the exhaust system is obviousely a testable item meaning not only must it be in good condition but also of the correct type.
Dave
alan s
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Post by alan s »

This is something that crops up costantly on bulletin boards particularly in UK. It would seem to be a little more complex than at fist it appears.
If you have a BX it was supposedly an optional extra pre 1993 so if you own a BX with a cat prior to that time there is no compulsion to have one for MoT. Many have done it without problems. The power gain I have heard described from "like pulling a cork out" to no noticeable difference.
One thing most do agree on though, and that is that after about 7 - 10 years the cat is is usually totally destroyed inside and not doing the job it was intended for. I am led to believe that a "high flow" cat can be bought if you want to play it safe.
Alan S
loe hofmans
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Post by loe hofmans »

Hello Dave,
I have my cat out and replace a steel pipe into the empty cat. in holland it was no problem with the emision-test they did not notice it!! ha,ha
My power (accelaration) is feeling twice as good, but the pipe gives some more sound
that is the only negative thing.
Good Luck, Loe
And yes I would do it again in my next Xantia.
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