What's the rules on catalytic converters?

[AuroraCab69]

Is it the age of the car that governs the need for a cat, or the age of the engine?
The reason I ask is a friend of mine reckons its the engine age. So for example if I put a 1990 engine in my 1993 (cat-equipped) car, I'd no longer need to have a cat.

[Astra Dan]

Re: What's the rules on catalytic converters?

That's generally accepted, although when I put a 1990 GTE 20XE in a 1996 Mk3 Astra, it needed to pass a cat test. So really depends on your friendly tester.
The law says noting about having a cat fitted, the car just needs to pass an appropriate emissions test.

[DarrenH]

Re: What's the rules on catalytic converters?

agree with dan. officially its this (direct quote from MOT testers handbook)

Test according to which is older, engine or vehicle.
e.g. A 1995 car fitted with a 1991 engine (of whatever make), test to 1991 standards for emission purposes.

Note: The onus is on the vehicle presenter
to prove engine age

but in my experience if they see a 1998 car, its a 1998 car. probably because they go buy registration plates for everything.

i would constest it though, because its not the bloody car thats creating the CO2, its the engine !!!

[screamer69]

Re: What's the rules on catalytic converters?

it goes by what evers older

if you put a xe from a 1990 cav in a 2001 car it will go by the engine not the car same as z20let in a 1990 car they will go by the car not the engine but you will have to prove the engine in some mot stations more so if there a nob and dont no there engines

it always goes with the oldest i have it it writeing somewhere if i can find it ill post it up lol

[AuroraCab69]

Re: What's the rules on catalytic converters?

Excellent news! So my nice old '89 age XE can go in my Astra Cab cat free! Woo!