MOT/emissions for engine conversions... definitive answer please!

Guybrush · 21 Dec 2006 at 23:38

If for example you put an engine from a 96 car into a 91 car, does it have to comply with the pre 93 or post 93 emissions regs?

Some people have told me they go on the vehicle; if the car is pre 93 it goes on the old test regardless of engine.

Others have said that it goes on the engine date, regardless of the vehicle it is mounted in.

Which is right, or can you just blag it whichever way depending on whichever suits you?

Iamzod · 22 Dec 2006 at 00:03

I checked this myself as i'm planning on putting a 1992 Engine out of a car with catalytic converters into a 1983 car that obviously doesn't have any.

MOT station said it'd be tested based on the age of the car itself.

Liverpool-Lad · 22 Dec 2006 at 01:29

Its based upon the engine, ie the thing thats putting out the emissions.

Glaucus · 22 Dec 2006 at 01:34

Here you go, your all wrong. It's which ever is the oldest.
taken from the official mot manual found at http://www.motuk.co.uk/manual_730.htm

Vehicles fitted with a different engine?

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.

Guybrush · 22 Dec 2006 at 01:34

There we have it... two mutually contradictory responses again!

Glaucus · 22 Dec 2006 at 01:35

Guybrush said:
There we have it... two mutually contradictory responses again!

check mine

Guybrush · 22 Dec 2006 at 02:03

yep cheers.

posted that before you posted.

next question then.

let's say you have a 1994 car and the cat is a bit knackered so it would fail emissions on the new test.

Now let's say you also own another of the same car, but a 1991 one. Identical engine.

You take the 94 car for an MOT and tell them that the original engine in it blew up so you bought the 91 car and transferred the engine. You present the V5 for the 91 car as proof.

Would they then test the 94 car on the old regs?

Would they ask for proof of engine numbers etc?

This is all hypothetically speaking of course

Psycrow · 22 Dec 2006 at 02:09

Its probably down to how good an actor you are

Glaucus · 22 Dec 2006 at 02:23

they would check the engine number as it's on the v5 and on the engine, isn't it?

Guybrush · 22 Dec 2006 at 02:50

hmmm... I don't recall.... I thought it was just the chassis number on the V5

I'd probably check when I get home if this wasn't hypothetical.

Dogbreath · 22 Dec 2006 at 08:20

If you perform an engine transplant on a production car, the emmisions test is still based on the age of registration of the car. If the car is on a 'Q' plate, it is treated as a pre-75 year for emmisions, i.e. visible smoke only.

If you are building a car (e.g. kit car) then you have to submit proof of the engines age at the SVA test, otherwise the engine will be treated as a post-95 (i.e. full cat test).

nutcase · 22 Dec 2006 at 10:51

My 83 car has a 93 engine, and it's done on 83 regs. Might be hard to get it to 93 regs as it's supposed to be 16v, efi and a cat. It's now 8v, carb and not cat

Malachy · 22 Dec 2006 at 13:04

i was always under the assumption it was done on whatever was the oldest out of the engine or car.with the owner having to prove the age of the engine if it was older than the car.