Practically Classics Forum

We try ro help where we can, looking forward to seeing the Imp.
On the subject of sunroofs, they do not automatically constitute a BIVA test.
We asked VOSA about sunroods when we were clarifying the monocoque definitions and they said this...

Q) Would the modification of wings to allow clearance for larger wheels fall foul of the regulations?

We presume not as the common fitment of sunroofs does not create issues as this is a non stressed item of the monococque, the same as wings?"

A) When considering a monocoque structure, it is necessary to consider what constitutes cosmetic panels that do not significantly add to the structural strength and which panels provide structural integrity. In general front wings modified in this way would not constitute a modification to the monocoque structure.

This this intimates that VOSA do not consider the fitment of a sunroof as something that affects the structural integrity of the monocoque, becuase the roof panel is geerally considered 'Cosmetic'.
Therefore, it's not a monocoque change and thus is not something that would result in a BIVA 'Invitation' on it's own.

Just a quicky for clarity
Am I right in understanding that for chassis based vehicles, fitting an alternate engine, and replacing or moving engine mounts is something that isn't classed as "Substantial modification".
but notching the chassis for clearance is.
The other question regards the bulkhead assembly. Mess with this on a monocoque, and my understanding is that this immediately gets you a BIVA as it constitutes a "Substantial modification" On a Landrover I'm presuming that this is also exempt as all the strength is in the chassis
Reason: I have a 6 cylinder Landrover that has a crappy engine that doesn't really live up to the promise, and fuel consumption isn't wonderful to say the least.
Part of me is thinking of dropping a TDi in there.
This will probably require me to move engine mounts, possibly bolt on a new bellhousing onto the gearbox, and maybe give a bit of a tweak to the bulkhead to allow bits not to catch.

From a landrover point of view I suspect that this may also catch people changing the body plan, even though doing this is basically spanner work, and heavy lifting. All sounds a bit OTT to me

On your 6-cyl Landy, the bulkhead will already be slightly different, won't it? ISTR noticing that the lower area over the bellhousing is set a bit further back so you may not need to modify it to give extra space.

Thanks for reviving this; I'd heard the engine-swap thing had been relaxed but hadn't realised that this only applied to pre-'73 vehicles... I have a '75 car that's undergoing an engine swap; good job I have all the papers for the donor as well as the recipient!

What sort of supporting paperwork should I pass onto any purchaser of my old engine?

SirTainleyBarking wrote:Just a quicky for clarity
Am I right in understanding that for chassis based vehicles, fitting an alternate engine, and replacing or moving engine mounts is something that isn't classed as "Substantial modification".
but notching the chassis for clearance is.
The other question regards the bulkhead assembly. Mess with this on a monocoque, and my understanding is that this immediately gets you a BIVA as it constitutes a "Substantial modification" On a Landrover I'm presuming that this is also exempt as all the strength is in the chassis
Reason: I have a 6 cylinder Landrover that has a crappy engine that doesn't really live up to the promise, and fuel consumption isn't wonderful to say the least.
Part of me is thinking of dropping a TDi in there.
This will probably require me to move engine mounts, possibly bolt on a new bellhousing onto the gearbox, and maybe give a bit of a tweak to the bulkhead to allow bits not to catch.

When we questioned DVLA on this issue, this was basically the summary of what they said..
http://www.the-ace.org.uk/Chassis-and-M ... ation.html?

It is acceptable to box original chassis and also to add additional crossmembers but not to alter the existing chassis in any way to allow for their installation.
It is acceptable to remove NON STRUCTURAL body mounts and engine / gearbox mounts.
It is NOT acceptable to shorten, or lengthen the chassis, either in between standard suspension points or fore and aft of these.
Any additional items welded creating a longer overall chassis are classed as modifications. It would however be acceptable to bolt a reasonably sized additional subframe to existing mounting holes.
Any outriggers (as opposed to continuous chassis frame) fore or aft from the chassis would need clarification from VOSA as to their purpose before removal or alteration was accepted. This would be based on their purpose and whether they formed part of the vehicles original Type Approval.

So, with the Landy example, you are correct, you can remove or reposition engine/gearbox mounts and put in a mew crossmember, but you couldn’t modify the existing chassis by shortening or lengthening it.
The bulkhead is not an issue for you are the vehicle is a ‘Chassis’ not a monocoque, so you can cut the body around as much as you wish.

OneCarefulOwner wrote:Thanks for reviving this; I'd heard the engine-swap thing had been relaxed but hadn't realised that this only applied to pre-'73 vehicles... I have a '75 car that's undergoing an engine swap; good job I have all the papers for the donor as well as the recipient!

What sort of supporting paperwork should I pass onto any purchaser of my old engine?

What DVLA are going to want to see from him is the origin of the engine so, what would really help him would be a photocopy of the log book for the donor with the engine number shown.

Although we have seen a swap accepted with just a note on headed paper from a 'garage', identifying the engine.

Willy Eckerslyke wrote:On your 6-cyl Landy, the bulkhead will already be slightly different, won't it? ISTR noticing that the lower area over the bellhousing is set a bit further back so you may not need to modify it to give extra space.

On the 6, the gearbox and crossmember is further back than on the 4. The propshafts front and back are different lengths to the 4. Yes the bulkhead has a wider transmission hole, and I think the 6 bulkhead was used in the stage one V8 for this reason
This was so that the longer engine could be buried up to the bulkhead without going the route of the stage 1 and moving the rad panel forwards.

I'm not sure about the difference in bellhousing between the 4 and the 6. The bolt patterns are different, but I think the bellhousing for the 4 is deeper.

Therefore I'm thinking use a 200TDi, and matching 4 cylinder bellhousing, and no adapter plate needed. If it pushes the TDi lump further forward, not an issue as there should be enough clearance, and the bonus being that access to the rear of the engine is improved a bit

I'm basically looking for better fuel consumption, reliability, and extra power. The 6 I have at the moment is lacking in all 3

1960Zody wrote:

OneCarefulOwner wrote:Thanks for reviving this; I'd heard the engine-swap thing had been relaxed but hadn't realised that this only applied to pre-'73 vehicles... I have a '75 car that's undergoing an engine swap; good job I have all the papers for the donor as well as the recipient!

What sort of supporting paperwork should I pass onto any purchaser of my old engine?

What DVLA are going to want to see from him is the origin of the engine so, what would really help him would be a photocopy of the log book for the donor with the engine number shown.

Although we have seen a swap accepted with just a note on headed paper from a 'garage', identifying the engine.

Brilliant; and as I have the V5C for the donor of my 'new' engine, that'll be my supporting paperwork too?

One thing that confuses me a lot is the rules around modification of the shell; I'd love to stretch an Allegro which of course has a monocoque, but it seems doing it at home automatically qualifies me for a Q plate although if I pay for a coachbuilder to do the very same work it might keep its original identity?

My thoughts that a stretch aggro would be amateur modified, BIVA, either original or age related plates. (IMHO, IANAL, all this stuff depresses me no end)

Most stretch limo's class as new builds, as a new car is taken then modified. The coachbuilder is the now "Original Manufacturer"

Yeah, like I said it's confusing; I'd like it to count as an Amateur Build and get a BIVA, but I can't be sure & I'd hate to go through all that work & end up with a Q. I know when the TG idiots made theirs, they all got Q plates but then they all made more than just a little stretch...