MG Sports Cars

Hi,

By way of introduction, I'm not yet an MG owner but will hopefully be acquiring a MGB (probably a '68 GT) in the next few months. I'm planning to fit a V8 so I'm working through what I can and can't do in light of UK regulations.

For those of you not familiar with the rules over here, a quick primer:
Any vehicle which has been significantly modified (engine change (not direct replacement), any modification to the suspension or chassis, etc. is notifiable) can be required to undergo a Single Vehicle Assessment (SVA), which is essentially an inspection to make sure the vehicle is roadworthy and complies with construction and use regulations. There are somewhat complex and vague rules to determine exactly how a vehicle is classified and therefore which regulations it is subject too. It would probably be impossible to get an MGB through the strictest tests, so I'll be doing my best to avoid doing anything that triggers them!

One of the key things is that there is a points system which determines whether the vehicle keeps its original identity. If it doesn't have enough points then it is issued a new identity and goes on a 'Q' plate. As well as the loss of the age related plates, for an older vehicle this means that it loses it's zero road tax status, and I think also means it must pass a host of rules that have come in since it was originally registered.

The points system works by assigning points to various parts of the vehicle. The vehicle gets points for each part which remains original and unmodified (direct replacement parts are generally okay). The chassis must remain as that is what actually carries the identity. So far as I've been able to work out it breaks down like this:

Total possible points = 14
Required to keep identity = 8

chassis (and body, for a monocoque) = 5
suspension = 2 (1 each?)
axles = 2 (1 each?)
steering = 2
engine = 1
transmission = 2

I thought the brakes were worth a point as well, but can't find that anywhere so it may be a figment of my imagination.

Obviously, dropping in a bigger engine in itself only loses one point, but then you have to account for knock on work. On '68 the steering will have to be modified for pretty much any V8. Anything but a very mild engine will need a gearbox change and uprated brakes. That's an absolute minimum of five points gone, six if the brakes count, for a remainder of nine.

Not sure if changing the front cross member for a rubber bumper one will lose an additional point - if it does, that's the entire allocation used up and no further mods possible without losing the identity. Looks like IRS, potentially even rear anti-roll bar, anti-tramp bars and telescopic dampers, are out (depending how strict they are), as is an uprated rear axle. I know plenty of people have go away with it up to now, but there's no point assuming this will continue to be the case - I'm currently involved in the UK Land Rover scene which has the same, if not worse, issues with modified vehicles and it's quite clear the authorities are clamping down. Besides which, it's just not worth finding out your insurance is void after and accident (which it would be if you've dodged an SVA you should have had)...

In light of this, how much power/torque would be a realistic target for a vehicle limited to the above? I want it to remain safe and driveable, so I'm clearly going to have to reign my ambitions in a bit...

Geoff

Geoff, I'm certainly no expert on UK motor vehical law, but it seems that if you duplicated the factory MGB GT V8 then you wouldn't incur any points as all the modifications were part of a production vehicle. Then you could make additional mods as required with some "cushion" on the points. Curtis has been publishing some articles in the newsletter recently about the origin of the MGB V8 with a lot of information that might be of help to you. Here's one such article [www.britishv8.org] You could use either a chrome bumper or rubber bumper car for a start as well.

Welcome Geoff!

Bill's thinking parallels my own... (I would have hoped that factory-spec components would get by without "points".)

I'm very curious to see what answers you get here on the message board, but you may also like to talk to some fellow UK engine-swappers to ask them directly what they've experienced.

Here are a couple recent "How It Was Done" articles:

Paul Avery of Essex: [www.britishv8.org]
(To send Paul a "private message", select UserID "paulv8".)

David Tetlow of Milton Keynes: [www.britishv8.org]
(To send David a "private message", select UserID "tetlow")

Darren Jones of Lancashire: [www.britishv8.org]
(I don't know if Darren has a UserID yet, but if you send me a private message, I'll share his actual e-mail address with you.)

We don't have Nigel Ricardo's car on our site yet, but his UserID is "kerbut". Hopefully we'll have many more UK-registered cars soon!

And...

Ken Costello & Roger Parker have been doing this forever over there.

I think that converting a 1.8 to factory V8 spec would still incur the same points penalties, as the vehicle wasn't registered as such. I could be wrong though - one of the problems is that the rules are not well publicised (or even easy to get hold of) nor are they consistently applied. 'Forever' isn't the issue - now is, and the rules have changed :(

Those are three very nice and very different cars! David's is closest to what I'm aiming for - I want to finish up with a car that looks more or less standard but has the sound and grunt of a V8. I'll ask them what they've had to do to put their cars on the road.

The GT I'm hopefully going to buy (it belongs to a friends father, but I haven't actually seen it yet) is a '68 on wire wheels. It's been in dry storage for the last 20 years and needs some welding to the sills - other than that I don't know much about it!

I've got the 3.9 Rover V8 from my old Range Rover (the car that got me hooked on V8s...) stripped down in the loft, which is likely to be rebuilt to go in the MG. Alternatively I could find a more modern engine instead. If an Audi 4.2 V8 fits that could be interesting - and possibly cheaper than rebuilding the RV8 - but at around 350bhp I don't think I could make it remotely safe without losing the cars identity :( There are plenty of engines that have as much power as the RV8 without its thirst - but also without that lovely V8 burble. The Range Rover was running Megasquirt'n'EDIS, which I'll probably use on this car too.

I'd like to fit LPG - at current UK fuel prices that car will get used a lot more if I do - but I reckon if it's feasible it'll only be by having no petrol at all rather than dual fuel. Too many weight and space issues otherwise. I reckon this could be done either using an LPI system or with an Eperspacher or similar pre-heater to prevent vaporiser freezing on an old style vapour injection system.

Geoff

I notice reading carefully through the specs of Paul, David and Darren's cars that they've all stuck pretty close to standard MGB specs (with an RV8 gearbox thrown in). I wonder if the SVA is the reason why...!

I suspect if more or less stock suspension is adequate on a track biased car like Darren's I don't need to be worrying too much about running out of points for making mine safe, though I could well end up with more power than him (the 3.9 RV8 was nominally 193bhp stock, can't remember the torque - even if I resist the temptation to do anything else to it* - I'll put a more performance biased cam in it).

* - yeah, right... :c)

Geoff,

I think the Audi V8 will not fit. Generally, the twin cam per bank 4 valve per chamber V8s are too wide for the B engine bay. I did a spot of measuring a couple of years back. If you want to use a modern 4 valve engine a 60 degree V6 is more likely to fit. Following your Audi theme, a 2.7 twin tubo out of the old S4 would do!

I have toyed with the idea of using a Jaguar V6 and manual box from the modern S-type. 240bhp as standard and a V6 should keep the weight down. I think the Audi V8 may be heavier than the Rover V8.

David

djw090 Wrote:
-------------------------------------------------------
> Geoff,
>
> I think the Audi V8 will not fit.
> David

Just invite Carl over with his chop saw!! He can make it fit! (Oh yeah, you might lose some points for a non standard body... just a thought. ;-)

Anything can be made to fit if you try hard enough :c)

As usual it's all very gray - would cutting holes for RV8 style exhausts trigger an SVA? Probably not. What about welding on reinforcing brackets for anti-tramp bars? Maybe... Substantially modifying the front of the chassis and body. Err... Somewhere in there is a line - but it'll be in a different place depending which official you talk too :c(

I've not managed to find any tech data other than power/torque/fuel consumption for the Audi V8, but you can pick them up for a few hundred pounds over here. Sounded tempting... I had considered that the V6 was a much more rational choice, but...it's got a couple of cylinders missing! I'd rather stick with the Rover, even though it's a vastly inferior engine. Makes no sense, but I'm not building a eurobox!

As an aside, are the V6's narrower because that cylinder arrangement suits a tighter angle V, or is it simply that they are packaged to fit in smaller cars?

Geoff

Geoff, because of the number of cylinders when you arrange them in a V type the crank seperation required to get a fairly even timed firing order usually dictates a 60 degree inclination between the cylinder banks. Same with a V12 by the way. V8s and V4s are normally arranged on a 90 degree inclination which makes them inherently wider. Add wide heads because of twin cams and they can get very broad. There are exceptions but these rely on somewhat complex and large internal balance devices to reduce unwanted vibrations or in the case of the Buick designed 3.8 V6 a split crank pin to help even out the firing impulses.

Geof,

The SVA regulations only apply to kit cars which require inspection by the SVA upon registration. A converted car only requires a MOT test and I do not know of anyone who has done a conversion having any problems with a properly converted car.

Kevin Jackson.

Kevin,

Modified vehicles are required to undergo the significantly more stringent Enhanced SVA if they are classified as a 'radically altered vehicle'. Kit cars fall under the 'amateur built vehicle' category and undergo only the standard SVA. Precisely what constitutes a 'radically altered vehicle' is the gray area.

For instance this vehicle was being stripped because it had been referred for an ESVA and (like any old Range Rover) would never have passed the current passenger vehicle regs. The full story of what Charles went through just to find out whether the vehicle needed an SVA is here. If you read that thread you'll find that at least one other person (with a much more heavily modified Land Rover) was just given the nod and issued a Q plate without having to undergo an SVA at all. In both these cases there were chassis modifications involved.

I've found a bit on registering a radically altered vehicle and registering rebuilt and kit cars. The first of these lists the official points system:

Quote:

* chassis or body shell (body and chassis as one unit - monocoque ie direct replacement from the manufacturer) (original or new) = 5 points
* suspension = 2 points
* axles = 2 points
* transmission = 2 points
* steering assembly = 2 points
* engine = 1 point

In the second it also clarifies that for axles and suspension both must be retained to keep the points. It does appear from the wording that adding to the components, e.g. by fitting anti-roll bars, probably wouldn't affect the points, but this may well be interpreted differently by different officials... However, the chassis/bodyshell must not be modified:

Quote:

The original unmodified chassis or unaltered bodyshell (i.e. body and chassis as one unit - monocoque); or a new chassis or monocoque bodyshell of the same specification as the original supported by evidence from the dealer or manufacturer (e.g. receipt).

From this it could be argued that even cutting holes for RV8 headers should lose the vehicles identity, and that a heritage bodyshell supplied with the holes was not to 'the same specification'... Depends how anal the official you get is.

I think from the above links that if the vehicle maintains enough points to retain its identity then it will also escape SVA. However, Q plates are sometimes issued without an SVA.

Going back to my original post, that would mean that if changing the front cross member loses the points for suspension, then a V8 conversion on a '68 would only be possible if the original gearbox was retained. It might be necessary to stick to block hugger headers too.

Geoff

So can you modify it some, get the plates, and then swap gearboxes or other parts?

Jim

You'd probably get away with it - no-one seems to be entirely sure what records are kept from these inspections, but potentially if you were involved in an accident (not necessarily your fault) and the vehicle was checked out and didn't match the records you could be in the doo-doo. Incorrectly registered vehicle and also therefore invalidated insurance (even if you've declared the mods to the insurance company).

I'm not even sure if the DVLA would know what to do if you contacted them to tell them you'd changed a gearbox - there's nothing on the V5 (vehicle registration document) that details it. However, the key here is that points list - changing the gearbox by itself just looses two points, but if it pushes you below eight points (even if you've previously been okayed with fewer mods) then you lose the vehicle identity and it's SVA (enhanced version) time.

Geoff,

When modifying the vehicle the key change is the change in engine as that has to be notified to DVLA. It can trigger an inspection to confirm the engine number and details are correct.

Provided you notify the engine change to DVLA the other changes are unlikly to generate an issue provided they have been notified to your insurance company.

David

Geof,

David is correct, provided the car has a valid registration is taxed or on SORN all you need to do is notify the DVLA of the change of engine and the new number. Gearbox, rear axle and suspension mods are not of interest to the DVLA and only apply at the MOT on a roadworthyness basis,

You obviously have to inform your insurers of any alterations to the vehicles spec.

My car built from a 1975 rubber bumper GT currently has a modified 3.5, 5spd g/box, narrowed SD1 axle,RV8 exhaust, coil over front suspension and reverse spring eye rear springs with telescopic dampers and I've had no problems whatsoever.

Even if you used a heritage shell provided you have an original vehicle with registration there is still no need to involve the SVA as its just a re-shell of an original vehicle.

Kevin