Thread: Gutting the Cat

I cut mine off and welded some pipe in place
Or you could buy a pre Eu3 down pipe and simply replace it

Chop it out and weld a pipe in!
I replaced the whole section with a terrafirma after market as needed a new flex coupling anyway.

I just spoke to an exhaust shop near me and they claim that to remove a catalytic converter is illegal ?

Really ?

Most developed countries have emissions laws requiring catalytic treatment of exhaust gasses to oxidise (add oxygen atoms to) carbon monoxide and uncombusted hydrocarbons. This is a good thing for urban air quality (particularly in high density population areas and areas prone to atmospheric inversion events) and greenhouse effect impacts (especially for uncombusted methane).

There is is possibly some argument for very high fuel combustion efficiency tuning of engines allowing a higher flow catalytic converter with less exhaust gas contact time, but that is a bit beyond my expertise.

Personally I would be be looking for performance improvements elsewhere and not gutting the catalytic converter... But your vehicle and your choice how to modify it.

Originally Posted by surfingooner

I just spoke to an exhaust shop near me and they claim that to remove a catalytic converter is illegal ?

Really ?

Yes it is illegal also removing your EGR is as well
Laws are made to be broken but don`t get caught
Do you have a mate that is handy on the welder or like i said earlier just buy a down pipe of a model that did not have the cat early D2 is your friend
And honestly whats a cat going to do on a Td5 for emissions any way

Originally Posted by rangieman

And honestly whats a cat going to do on a Td5 for emissions any way

Given that sulphur is the enemy of cats, and Aussie diesel was high in sulphur content until a few years ago ( About when the first HiPo diesels appeared in Audis and Beemers locally ),
I'd say "not much". Happy to be corrected on that though.

Originally Posted by surfingooner

I just spoke to an exhaust shop near me and they claim that to remove a catalytic converter is illegal ?

Really ?

Any mod that interferes with emission controls that are mandated under ADRs is illegal. Lots of workshops fell foul of the EPI for removing devices that were fitted for ADR 27A compliance. Anyone who remembers the strangling effect of those mods back then (1986? ) would understand why people took the risk though.

Me, I'd get rid of it. The only way you'll get done is if you drive through an EPI test site, and, as rangieman says, I doubt they'd notice, as the cat is probably doing nothing.

Thanks Gents, since the EGR is long gone, in for a penny in for a pound I say. Yes I spoke to friend this afternoon, has a worshop as he re-builds pre-war cars for a job and he said he has welding gear and a spare exhaust I can cut up. Three questions if I may:

1) Cut the pipe, de-gut and leave the converter box on and re-weld, or just get rid of the whole converter - been reading that smooth pipe all the way is the best way ?

2) if cutting, do I still have to remove the cross-member ?

3) if I have to remove the cross-member, can I do a 10km round trip without it ?

I have a daughters basketball game in middle of afternoon so we have a 3 hour window to do the cutting and welding. As I have never welded before and he has offered to do it, should I remove the cross-member beforehand or will we have enough time to do everything in 3 hours ?

Please excuse my ignorance with this !!

Thanks again, Matt.