What happens to road tax when you change an engine?

[Deva Link]

TheLurker said:

ny of the items mentioned, such as colour change, don't affect the tax.

So you could buy a post 2001 car with a 1l engine in, dump a 3l v8 in it, and still be charged £30(or what ever the 1L engine was) a year tax?

Yes.

In reality, how many people are going to do that? And anyway, these days many engines offer a range of outputs by changing the size the of the turbo, the injectors and the engine map, so that would be easy to do.

If it was thought to be happening a lot then there would be a crackdown.

[Deva Link]

jbi said:

supersingle said:

I believe this loophole is on the EU radar, it certainly is for bikes where they are planning to outlaw any modifications from the engine, through the transmission to the driven wheel.

All in the name of safety and tge environment dontcha know.

This will kill off a huge industry if it ever makes law... more meddling with the market economy.

I think it's the case already in Germany that you can't mod anything on a car without it going through a VOSA type inspection.

[mcford]

hungry_hog said:

Also, if it's an older car the CO2 emissions would appear on the MOT so VED may change from that

They measure CO on the MOT not CO2.

[kambites]

Martin Keene said:

The presumption there is they have also changed the V5. For cars registered before 1st March 2001 there will only be a change in the VED if you go from below 1400cc to above 1400cc or vice verse.

What the hell happens for a car registered after 1st March 2001 where it is all done on CO2, I have know idea. You can't put the car though another c0" test, so I assume it remains the same.

Yes they have all changed the V5 and most of the cars are registered after March 2001. The cars are all still in their old tax band (which is less than they would be if taxed by capacity).

Edited by kambites on Sunday 9th January 10:18

[Compo_Simmonite]

I enquired about fitting a 1.5 diesel into a pre March 2001 1.6 Vitara that would bring it into the lower road tax band. DVLA said I would need confirmation from motor engineer, garage etc that the engine was of lower capacity and they would then change record.I was advised that I COULD be required to take vehicle for an inspection but it wasn't always necessary in all cases.
They did, however, tell me that with a post March 2001 vehicle a full inspection would definatley be required in all cases
From reading in recent motoring magazine it's now a PIA to change any engine from standard as you need to provide "providence" for the transplanted engine - ie details of the donor.

Paul H

Edited by Compo_Simmonite on Sunday 9th January 10:32

[steve_amv8]

swerni said:

They only have emission figures for cars officially sold in the UK, hence my Stang and Camaro are both taxed as above 1.4l.

Interesting ... so £205 a year in tax?

[shovelheadrob]

Just been through this with a custom bike I have been building for last ten years, sent V5 off to Swansea for change of engine no & capacity, got letter back requesting receipts for everything, i.e.bill of sale for parts, invoice from garage that fitted engine etc. I explained that the engine came from a bike I owned 30 years ago & sold on with a different engine (so no receipt) & that all the work was carried out by me (I offered to do myself an invoice but they said no). I was then told that unless I got a local bike shop to inspect it & authenticate the engine etc that no details (inc change of colour) would be to the V5 & that a new one would be sent to me un-mended.
Well a few days later new V5 arrived complete with all changes made, cc, engine no & colour! It has saved me a right headache as I can't imagine my local Honwamazuki dealer being able to identify a 30 year old Harley engine in a highly modified 50 year old frame!
I will not condemn the DVLA for incompetency on this occasion, although it may appear that the left hand is unaware of the right sometimes it can be an advantage.
It ued to be that if you went up in taxation class then they took your word for it, but wanted proof if you were going down i.e. cheaper tax, but now they just don't want you doing anything.

Edited by shovelheadrob on Sunday 9th January 10:55

[shovelheadrob]

steve_amv8 said:

swerni said:

They only have emission figures for cars officially sold in the UK, hence my Stang and Camaro are both taxed as above 1.4l.

Interesting ... so £205 a year in tax?

Yep same as my supercharged Roush F150, it's a loophole that any vehicle not officially imported falls into this, three cheers for the DVLA!

[andy43]

Pre 2001, if you go up or down through the 1.4/1.5 cutoff, they could amend your tax rating.
After that, with tax based on CO2 it's impossible to work out what the emissions may or may not be post-V8 transplant. So it stays the same. For now - Yerp may have plans to change that.
Small producers like Alpina, TVR etc, or imports where emissions haven't been tested are also 'plg' class even post March 2001 - so my Alpina is less to tax than my OH's Beetle. Shhhhhhhh.

[ALawson]

I reckon that they would base it on the pre march 2001 criteria i.e. engine size above and below 1.8l(?) as there is no way of working out the CO2 of the new engine easily.

I was thinking about this very same thing when I thought my ATR tax was going to be £425 (before they change it to pre 2006 registered cars).

[aw51 121565]

The cut-off in engine size for lower/higher vehicle excise duty rates is 1549cc.

Anything with an engine over 1549cc pays £205 p.a. if it was first used (it's a bit more complicated than this, but this will sort out 99% of cases) pre-March 2001.