I'm going to jump onto this quite quick before it gets blurry.
IVA and SVA requirements have been hotly debated for over a decade. In this time we've seen dozens of opinions and views on different interpretations of what is allowed and what isn't. Some people quote precedent (like "Mark Evans did it to his 100" on TV) others have different views of what you can do and what you can't. It was historically so hotly debated that some forums actually banned the topic entirely.
The information on what constitutes a radically altered vehicle are detailed on the government websites. However they fail to go into specifics on what constitutes a modified chassis and typically assume a monocoque construction. This results in huge amounts of grey areas and the information is inconsistent within DVLA and VOSA (now DSVA).
What virtually all miss is that
it was clarified at the time by a now defunct car club that focuses on custom vehicles, at the time called the ACE.
They had a long, very detailed interview - with follow-up with the inspection bodies and clarified specifically what you can and can't do. The ACE website closed years ago, but I copied the transcript before it closed.
Here it is for prosperity:
"
Quote
Chassis and Monocoque Modification
VOSA Clarification on Body/Chassis points rules
Some of you will have taken the time to find the rules that govern how much you are allowed to modify your vehicle before its identity is called into question.
Whilst the 8 points system has been in place for at least 27 years (in its current form) DVLA have been sadly remiss in making the guidelines relating to car modifying known to those that it affects.
We will shortly be adding articles to show how the system works in relation to various vehicles but this is the description as published by DVLA.
Rebuilt vehicle 8 points system: -
An existing vehicle uses a similar system: -
The guidelines shown above are not specific about their application.
ACE have attempted to clarify certain areas that go to the very root of a car's identity, and how much you are allowed to modify the chassis or monococque, before you lose the 5 points it represents.
We have been liasing with both DVLA and VOSA to clarify this area.
Initially we received this reply from DVLA:
"When assessing a modified/rebuilt vehicle, DVLA's main interest is to establish whether the original identity has been compromised by the changes made. If a vehicle has been modified from the original manufacturer's specification or if not enough of the original components have been retained in the build, the vehicle identity will change and IVA will be required to register with an alternative registration number.
Due to the very nature of rebuilding or modifying vehicles from their original manufacturer's specification, DVLA assesses each vehicle on its own merits based on the documentary evidence provided and a physical inspection of the vehicle.
The INF 26 information leaflet, and the information given on the website, is issued as a guideline to the registration of rebuilt, radically altered or kit converted vehicles. They are not meant as technical guides. However, both clearly indicate that if modifications are made to the chassis or monocoque bodyshell, or if the build does not include enough original, major components (as listed) the identity of the vehicle will change.
The information on www.direct.gov.uk is regularly reviewed to reflect changes in legislation
VOSA have provided the following response to your questions;
Chassis.
Q) What is classed as chassis? Is it purely the outer longitudinal rails or are the crossmembers between these also a part of the chassis?
A) Chassis should be taken to include crossmembers.
Q) We know that cutting or shortening a chassis is classed as modification but is this relative to the vehicle wheelbase i.e. the chassis must remain uncut between the 2 axles but anything forward of front or aft of rear suspension mounts can be removed?
A) Chassis includes the full original length of the longitudinal members including to the front of the front axle and to the rear of the rear axle.
Q) Is it acceptable to remove bodymounts, which contribute no strength to the chassis when changing a body to a different style /make?
A) Yes, providing they are additional to and are not an integral part of the chassis structure.
Q) Is it acceptable to strengthen a chassis by the addition of boxing plates a process that involves turning a 3-sided open chassis rail into a fully enclosed 'box' chassis?
A) Yes, providing the original structure remains unchanged.
Monococque.
Q) What is the definition of a monococque ?
A) A design in which body and chassis are all one unit.
Q) Why does cutting into a monococque affect the vehicle identity if it retains the same shape /profile as before.
A) Cutting is considered to be modifying the vehicle from its original specification. Any modification to the chassis/monocoque body is considered to render the vehicle no longer original specification or of original identity.
Q) Is it acceptable to modify a vehicle bulkhead and/or transmission tunnel when performing an engine change or fitting another make?
A) No, Assuming this is in relation to a monocoque structure. This would be considered a modification to the structure.
Q) Is it acceptable to fully weld sections that are spot-welded as part of the original construction methods, to increase the strength of the body?
A) Yes, providing the original structure is retained.
ACE felt that further clarification was needed from VOSA so we sent more questions.
The following responses are from the VOSA Press Office:-
The answers to our chassied vehicle rules queries seem mainly straightforward, However, we have further questions based on the answers supplied.
Q) As chassis strengthening is allowed, are we correct in assuming that additional crossmembers would also be allowed?
A) It is important that the original chassis structure is retained unmodified, and while it is acceptable to strengthen areas and include additional brackets or crossmembers, It would be limited to additions within the existing chassis frame structure. Additional chassis structures, i.e. extending the outward parameters of the original chassis structure would be considered a modification.
Q) It is the monococque rules that need the most clarification.
Your reply states that any cutting of the monococque" is considered to render the vehicle identity no longer original specification or of original identity ". This would suggest that any crash repairs necessitating cutting and removal of panels or chassis sections, or restoration work would call the vehicle's identity into question?
We presume that the point should really be that any cutting... other than in factory designed joining areas...would be the actual criteria?
A) In this respect it is necessary to differentiate between modification and repair. Any repair process that is in line with manufacturer's recommendations and that returns the structure to its original specification would not be considered to be a modification.
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.
With reference to the further query, VOSA have advised that they would prefer the following statement:
What constitutes a monocoque is that of how an OEM manufacturer would view it. The chassis or `cage` assembly and all components that form it, less any cosmetic panels or infills that make no structural consideration to the monocoque or its component parts.
However, we must emphasis that this information is given for general guidance and each case will be judged on its merits.
Whilst none of this is definitive, and it contains the usual 'Judged on it's own merits' criteria, it does answer a lot of questions where the modifier has only been able to speculate in the past.
It means we are aware of what we can or cannot do and still retain the 5 points from the start of any modification process.
So, to summarise the above information:
Chassis
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.
Monococques
It is NOT acceptable for the bulkhead, or transmission tunnel area, to be modified.
The specification for a monococque will vary with each manufacturer and the decision on what are acceptable modifications will be based on those criteria for each vehicle.
It is acceptable for additional seam welding to be carried out.
Should there be any further questions relating the above information on specific vehicles ACE would be willing to assist in further clarification on an individual basis.
The above information relates to only 5 points (awarded for original unmodified chassis / monococque) of the 8 points system for retaining vehicle identity and we will be clarifying other sections in the future."In basic terms, none of the government agencies really know - so the above is as close to precedent and technical details as we're ever likely to get (though it was not published by an official source) - so it will come down to each owner's interpretation of the above and whether they are willing to fight legally.
I wanted to avoid giving an opinion as I am absolutely no expert and have merely read the information, but it is probably unavoidable, so in Land Rover world: my very personal (and very risk averse) interpretation is this:
1) I wouldn't move/chop or modify any of the crossmembers or chassis rails.
2) If I were so inclined, I would be comfortable in removing and fitting different ancillary brackets (engine mounts and mounting tabs).
There is a well publicised issue with a Mini EV conversion that I'd guess you've read recently, where they pulled the owner up for drilling a hole in the battery tray of a mini chassis. As ridiculous as it is, it isn't something I would have done as its technically removing material from the shell that isn't a standalone ancillary bracket.
Beyond the above, there isn't a lot more information out there - the only real test is to find people who have had issues flagged and to see their experience of how DVSA have handled the issue. The only one I'm aware of is the unfortunate chap with the mini.
Our VRO may have far more insight than I.
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Topic: Extra chassis adornments. What can you weld on and chop off. (Read 2515 times)
