Restoring the Clairmonte Special

David Harvey and I recently bought the Clairmonte Special at auction. This car started life as the Lotus Mk VII single seat Formula 2 car with a Riley six cylinder 2 litre engine, but before it was completed at the Lotus works at Hornsey in 1952 it was removed by its owner (Clive Clairmonte) and changed into a two seat sports racing car with a 1.5 litre Lea-Francis engine. It raced with this engine in 1953, and was then fitted with a 2 litre Connaught engine, which it has kept until now.

We have started a restoration and will need your help to identify components. The engine and Lea Francis gearbox have gone to Beaufort Restoration at Sittingbourne in Kent. I have just removed the radiator which bears the following label:

BRITTOL RADIATORS LTD
WEDNESBURY NO 17
COVENTRY No 6

The nembers are hard to read and may be wrong.

Do any of you know of this company and what became of it? Any suggestions as to where we could have it checked over?

LOTUS MK VII REPLICA

We intend to build a replica of how the original Lotus would have looked as a single seater, and will need to make copies of the components on the Clairmonte. Any ideas for where we could have a copy of this radiator made?

This is the first of many such requests as we progress with the restoration.

For photographs and more on the history of the Clairmonte Special see the Historic Lotus Register website http://www.historiclotusregister.co.uk and click on "Cars" and then the small photo next to "Lotus Mk VII".

Seems strange that they would have gone such a long way to get the radiator made, or was the car finished in the midlands, or was the radiator changed when the engine was changed?

Serck have a historic department that are very good (they can supply many radiators from the original drawings that they still have), they could rebuild the radiator for you.
Not sure where they are but you should be able to find them via:
www.serckservices.com

If not there was a company in (I think) Wales called (something like) Star Engineering who produce things like Lotus 20, 22 & 23 radiators as well as Bugatti ones.

If you only want to pressure test the existing radiator, rather than rebuild it, you should be able to find a local radiator place who can do so - there are less and less in today's throwaway society, but commercial vehicles still rebuild a lot of items wherever possible.

By the way if you are going to fit a 6 cylinder Riley engine (ERA or normal?) you should talk to Barrie Gillies - he has prepared more than anyone else and can give you an idea of what you will need (there are several types of RIley 6 cylinder, and some items like manual gearboxes can be hard to find - n.b. make sure you are sat down when you ask about prices!).

Congratulations on the Clairmonte Special-I was really intrigued with the car as advertised-glad it stayed in the UK. I hope you get the car finished before starting to build the replica single seater-I think that will be a very expensive proposition.

The previous owner of the Clairmonte lived near here: he restored an old piece of furniture for us.
I took these photos at the time. ( I hope me posting them is OK with you, Peter)

I’m posting this for Peter Ross…..

Help needed to identify parts

I have now dismantled most of the front end of the Clairmonte Special,
and need to identify the proprietary components that Colin Chapman used.
Some of the photographs show the rack and pinion, which I am assured by
a Morris minor expert is NOT from a Morris Minor. It bears the name
MOWOG on the body casting, placing it firmly as a Morris, Wolseley or MG
part, but don't forget that in 1952 there were not may cars with rack
and pinion steering. The most likely is the Morris Oxford MO, but the
TD MG is another possibility. It has stamped onto it 1F3327 or 332/.

The front suspension uprights are from a car that has rack and pinion
steering, because there are tapered holes for the steering arm on each
side (with a keyway), but no additional arm to connect with a drag link
on the RH side. There are no parts numbers visible. The part with the
front axle spindle is detachable, and is fixed by the same bolts which
hold on the brake back plate.

The brakes are almost certainly Girling 2LS 11" diameter from an Austin
A90 Atlantic, and if any of you know where I could buy a set of front
and rear backplates with brake shoes and cylinders I would be most
grateful. We also need two rear brake drums from the same car. The
front drums are Alfin and we will probably get them made by Typecast
Engineering Ltd .

The last posting on this subject was in February 2005. Quite a lot has happened since then so I am sending this by way of an update.

Rack and pinion

Despite the "expert" advice that it is NOT from a Morris Minor, there is now no doubt that it IS, but machined to allow different sized clamps. Thank goodness one can get these racks quite easily and at a reasonable price.

Front Suspension Uprights

After going frantic in my search for the proprietary parts from which these were made I took a closer look at the photos of the Clairmonte BEFORE it was completed, and although they are a bit fuzzy it is now clear that these black-painted uprights were a later modification by Clive Clairmonte for the 1954 season.

From Sebastian Clairmonte, Clive's nephew (who was 16 at the time), I have been told that when Clive Clairmonte took the car to Goodwood it was not passed by the scrutineers. They were not happy with the front suspension. I think that it was the steering arm to which they objected, and this is what made Clive fit this tubular member around the original slender upright, to which he welded part of a TD MG upright to get the emplacement for the TD MG steering arm which is now fitted, and was NOT on the 1953 car.

What I thought was a forging from a production car turns out to be a very neat bit of fabrication and welding, followed by a lot of filing to give the appearance of a forging. Needless to say we will revert to the original Chapman design for the replica, and hope that the scrutineers are now better educated. The set-up is very similar to that used on the Kieft 500 raced so successfully by Don Parker and Stirling Moss. It incorporates Ford Ten stub axles!

The new front upper wishbones have been made and material sourced for the lower streamlined wishbones. A Halibrand axle obtained from the USA and parts are being machined to fit this to take the inboard rear brakes. The de Dion tube and bearing housing have all been drawn out and parts are being machined and a jig is being made.

All this has been made easier by keeping the Clairmonte in pieces so that drawings could be made. The next stage is to start to build the narrow single-seater chassis frame. We have bought a Riley 6/15 engine and are getting advice from Steve Davie who owns the ex-Hector Dobbs Riley whose engine was to have powered the Mk VII. We are looking for a suitable Riley manual gearbox.

I will be happy to answer any further questions.

Have I got this right?

You are producing two cars:
(a) A restored Clairemonte Special.
(b) A replica of what the Lotus Mk7 would probably have been had Colin Chapman completed it

If this is the case, how are you addressing the question that all restorers of specials have to answer - What stage of the car's evolution am I going to restore it to? I'm not being picky, I am genuinely interested in how you make a decision like that.

Thank heavens there are still people dedicated enough to take on these tasks.

Thanks for your interest D-Type.

In this case the question of to what standard it should be built is an easy one to answer as it never actually moved under its own power as a single seater.

We will use the condition it was in when collected by Clive Clairmonte from Hornsey and as far as possible build it as it was in 1952 before the chassis was widened and a Lea-Francis engine fitted.

The mountings for the Riley engine had already been made and fitted, I remember Nigel Allen (happily still with us) tacking it onto the chassis at Hornsey with the engine block upside down on the floor. It was lighter to lift the chassis on and off the engine than to lift the heavy engine out of the chassis!

The front suspension will be brought back to the standard Colin designed and Lotus had built, and this would be without a roll bar (which the Clairmonte now has but was fitted for the 1954 season when they put in the Connaught engine).

What is going to be the only major guess is what the body would have looked like. I feel that the rear end would have been very similar to the Lotus Mk III, and the front fairly square like the Lotus Mk VI (but not quite as wide).

I would love to have sketches from anyone interested enough to suggest how it might have looked.

This seems to have passed me by Peter; I hadn't realized this machine was now within your curtilage, so to speak.
Is there much information on how its details would have been had Chapman's and the factory's involvement continued as planned? Or will you have to make some speculations? Either way, a fascinating project.

As a more whimsical aside, had this car been finished as the Mk 7 single-seater, what would the subsequently-named Lotus Seven have been called (assuming not Seven)... Eleven B? Or "14" perhaps, with everything else moved along one number?

Edit:
Ah... you seem to have answered most of my first (and principal) question! Thanks.

Riley 15/6 manual gearboxes are quite rare.
Barrie Gillies has a huge amount of experience with 6 cylinder Riley engines.
He makes a lot of parts for them, including gearbox parts - he will give you some idea of what the options are and the weak points.
http://www.barrieagillies.com/
If you haven't done so already it is probably worth talking to Barrie.

Another major Riley specialist is Ian Gladstone's Blue Diamond services:
http://www.rileycars...co.uk/index.php

Peter, can you tell us a bit more about the history, chronology and who chose the componentary.

Looking at David Beards pictures the suspension looks heavy and not typically Lotus in any way. What would have been made in the Lotus factory, or has it just been drastically altered over the years, are there any photos from the period it was made ?

25-001 - could this be the basis of a possible"Low Flying" article?

Here is the owners' brief history of the Clairmonte's construction:
Harvey and Ross page on the Historic Lotus Register website (starts about halfway down the page)

at the risk of asking a stupid question did it ever actually race? If not what are you going to do with it when completed as it wont get FIA papers so you will be pretty restricted. I am probably missing the point!

Riley Experts

I have already been to see Barrie Gillies and will bear in mind the Blue Diamond connection. The most helpful person so far has been Julian Majzoub who owns and races the ex-Dixon Riley which has virtually the same engine. He has agreed to help with the engine spec. and tuning and his nephew will be doing the engine.

Front Suspension Weight

The upper front suspension wishbone is a fabrication made from 16g sheet steel edge welded. I have just weighed the one we have made for the replica and it comes out at 4 lb and 5 oz. I think that is pretty light for a cantilever wishbone taking all the suspension bending loads. It would look more elegant as a curved shape as on the 1961 Lotus Type 24, but that was after Chapman had had a further ten years experience.

Written History

This is covered in depth in my book "Lotus - The Early Years 1951-54" (Coterie Press), and there was a four-page article in the Historic Lotus Register magazine for Winter 2004 (copies of which are still available for £5 plus postage!).

You can see a good photo of the chassis as it was in 1952 on the HLR website as referred to by Charles Helps.

Can it be raced?

I have been assured by the VSCC that the precedent set by the 1954 Kieft, which never moved under the power of its 2.5 litre Climax V-8 engine until a few years ago, will allow the Lotus Mk VII replica to race in VSCC events. Once that has happened, and if there is sufficient interest, I have no doubt that other invitations will follow. The Kieft raced at the Goodwood Revival in 2005, and I reckon Chapman's first single seat design is of even greater interest.

Plea for help with Chrome Plating

The front suspension was chrome plated, and we need to have this done for the replica, and for the original parts to be stripped and the rust removed and re-plated. There is a grave risk of hydrogen embrittlement unless the parts are heat treated after the plating process. Does anyone know a reputable UK firm that could do both processes?

Originally posted by PeterTRoss
Riley Experts


Can it be raced?

I have been assured by the VSCC that the precedent set by the 1954 Kieft, which never moved under the power of its 2.5 litre Climax V-8 engine until a few years ago, will allow the Lotus Mk VII replica to race in VSCC events. Once that has happened, and if there is sufficient interest, I have no doubt that other invitations will follow. The Kieft raced at the Goodwood Revival in 2005, and I reckon Chapman's first single seat design is of even greater interest.

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There is also the matter of the Walker Climax, which, IIRC, never raced in period but which is accepted and readily invited to the relevant meetings, plus, form an historic point of view, the car's significance should see it invited, IMHO.

re Riley/Era engines, perhaps Alan Burnard, via VSCC, may be able to offer help as he made his own ERA engine for his ERA Delage, plus making new blowers for them, as told most lucidly in his narrative in the VSCC Bulletin a while back, so he knows what fits/works etc, plus possilbe contacts.

Roger Lund.

PS, the book is excellent.

Originally posted by PeterTRoss

Plea for help with Chrome Plating

The front suspension was chrome plated, and we need to have this done for the replica, and for the original parts to be stripped and the rust removed and re-plated. There is a grave risk of hydrogen embrittlement unless the parts are heat treated after the plating process. Does anyone know a reputable UK firm that could do both processes?
[/FONT]

Derby Plating services are very good (their address, number etc can be googled easily enough).
They have a Rolls Royce connection which gives an indication of their standards (and prices), they will know about hydrogen embrittlement.

As far as the problems caused by hydrogen embrittlement I've never come across a problem with it, but have seen other failures due to polishing the welds/brazes on components prior to plating.

Your rocker arms might be more highly loaded than a normal wishbone, but Lotus 21,24/25 & 27 etc rocker arms work fine when they've been plated and by the looks of it they are probably less over-engineered than yours.

Either modern plating is better (or they are more aware of the issue) or embrittlement isn't as big an issue as it was made out to be 30 years ago (the time they banned chrome on F1 suspensions - which again are far higher loaded).

Originally posted by bradbury west

There is also the matter of the Walker Climax, which, IIRC, never raced in period but which is accepted and readily invited to the relevant meetings, plus, form an historic point of view, the car's significance should see it invited, IMHO.

There is a big difference with the Walker Climax and Kieft (plus various un-raced F1 spare cars in TGP etc). Both those were as they left the factory - the Walker Climax being a complete car that was tested but never raced, the Kieft was a complete rolling chassis that was never completed with an engine.

They are the entirety of those particular F1 projects, they weren't converted into other cars and are totally original - having never been dismantled until they were prepared for historic racing.

I appreciate this project and am interested to see how a Riley powered Lotus will go (having a lot of experience of both makes), but think it is unfair to compare such a project with original cars that were simply unused.

The question of originality is this case raises some interesting points for debate.

It seemed to us that we had a choice of two possible actions:

a) To restore the Clairmonte, and build an exact replica of the Lotus Mk VII as had been designed by Chapman.

b) To remove all the changes made to the car to turn it into a two seater, and build it up as the single seater using all the original components. The Mk VII would then not be a replica. We could then build a replica of the Clairmonte. By doing this we would destroy a car that has its own history of competition.

Our choice has been action (a). This allows all concerned to examine the Clairmonte to see just where the tubes were cut to change it into a two seater, and the various changes that were made during its racing career.

Action (b) may have made the car more eligible for racing in historic events, but the sacrifice of the heritage of the Clairmonte seemed to us too much to countenance.

I would be interested to hear how others would solve this dilemma.

PS Thanks Peter for the tip about chrome plating.

Where can I read about the Walker Climax?

Originally posted by Peter Morley


There is a big difference with the Walker Climax and Kieft (plus various un-raced F1 spare cars in TGP etc). Both those were as they left the factory - the Walker Climax being a complete car that was tested but never raced, the Kieft was a complete rolling chassis that was never completed with an engine.

Peter, that was the purpose of my posting, mindful that they never raced in period, but are happily accepted now. I am totally in support of the Clairmonte being allowed to race. PR's policy is first rate and to be applauded. His option b seems rather akin to a version of the restoration of the Multi Union as a tipo B monoposto.

RL

I have seen chrome suspension arms fractured in the past , something not uncommon on early Lotus. I think it is a risk not worth taking if it can possibly be avoided. Bright nickel looks good , yes it does need polishing to keep it sparkling but that would be my choice.

Originally posted by PeterTRoss
The question of originality is this case raises some interesting points for debate.

It seemed to us that we had a choice of two possible actions:

a) To restore the Clairmonte, and build an exact replica of the Lotus Mk VII as had been designed by Chapman.

b) To remove all the changes made to the car to turn it into a two seater, and build it up as the single seater using all the original components. The Mk VII would then not be a replica. We could then build a replica of the Clairmonte. By doing this we would destroy a car that has its own history of competition.

Our choice has been action (a). This allows all concerned to examine the Clairmonte to see just where the tubes were cut to change it into a two seater, and the various changes that were made during its racing career.

Action (b) may have made the car more eligible for racing in historic events, but the sacrifice of the heritage of the Clairmonte seemed to us too much to countenance.

I would be interested to hear how others would solve this dilemma.

PS Thanks Peter for the tip about chrome plating.

Where can I read about the Walker Climax?

Tricky isn't it:

B, removing all the changes to turn the Clairmonte back into a single seater would leave you with a car that hasn't got many original components and if it never raced(?) in that form might be difficult to get accepted (but acceptability can have a lot to do with who is driving and how fast it is).

Of the two, A makes the most sense - keep the Clairmonte as original as possible and build a Mk VII that is as accurate as possible.

Option C could be to just restore the Clairmonte and say that Mk VII is gone forever.

And options D, E etc would cover using various different engines that the Clairmonte ran with over the years!

Converting a car back to its 'original' form is always tricky, most end up with so few original components it is hard to see the difference between it and a replica - but in some cases it is the only option, if you want to use the car, if there are no events for the later version for example.

Building 2 cars out of one (like the Multi-Union and lots of Bugattis) is always controversial, and there won't be many original components in either car - but in some cases it made financial sense (fortunately that is starting to change with Bugattis - completely original cars have recently made far more than you would get for the 2 or 3 bitsas that could be derived from the 1).

So 1 car as original as possible and 1 replica that is as accurate as possible is certainly the preferable solution from the point of not destroying history, and should increase our historical knowledge by letting us see a Mk VII (as with the earlier cars a replica has to be better than nothing).

There is some information on the Walker Climax on this forum - the thread about F1 cars that never made it has photos for example.

Originally posted by Peter Morley


Tricky isn't it:

Building 2 cars out of one (like the Multi-Union and lots of Bugattis) is always controversial, and there won't be many original components in either car - but in some cases it made financial sense

Perhaps an expert can explain to me where the Multi Union is now?

RL

Roger. I think the remains of the Multi-Union are or were owned by the late David Blacks son

Is it me or am I missing something here when the debate is about radiators and chroming? The "Lotus" bit was unfinished in 1952. What would the car have been if completed, a club special powered by a 20 year old engine? The Clairmonte Special, this hardly set the International motor racing scene alight at the time.
I am personally indifferent how the owners of the car restore/split-up/recreate the car(s). If it were mine I would be delighted to own a 1950s club racer with an interesting history and "a hint of early Chapman" in the chassis.

Thats what I was thinking "Squire" How can you build something that never was !!! Are there any Chapman drawings of the finished article ??The Clairmonte was a nice special and thats how it should remain.

Originally posted by Squire Straker
Is it me or am I missing something here when the debate is about radiators and chroming? The "Lotus" bit was unfinished in 1952. What would the car have been if completed, a club special powered by a 20 year old engine? The Clairmonte Special, this hardly set the International motor racing scene alight at the time.
I am personally indifferent how the owners of the car restore/split-up/recreate the car(s). If it were mine I would be delighted to own a 1950s club racer with an interesting history and "a hint of early Chapman" in the chassis.

I think the idea is to restore the Clairmote Special as that, which as you say is an interesting club racer and as such deserves restoring (and keeping as original as possible), which is as much as most owners would be happy with.

Then there is the issue of building a Lotus Mk VII to see what might have been (which has been made easier by having access to the Clarimonte).

There were very few modern engines around at the time - Bristol engines were old BMWs, Alta engines were based on the Lea-Francis which is similar to the Riley, etc.
Plenty of cars (at least British ones) at the time would have used engines that were also 20 years old, and very few had anything like Chapman's design skills.
If the Lotus VII had been built it might have been successful, but the performance of other ERA engined F2 cars would suggest not.

As others have said it will be difficult to make a totally accurate Mark VII, and I'm still not convinced that a replica of an unfinished projects is acceptable - the Kieft etc are different since they were unused rather than unfinished and are very original cars.

Originally posted by Peter Morley



Alta engines were based on the Lea-Francis which is similar to the Riley, etc.

Without wishing to detract from the validity of your point I should say that the Alta dohc engine has nothing whatever to do with the high camshaft Riley and Lea Francis engines. The Alta engine first appeared in 1928 in 1,100cc form and was gradually developed into the 2 1/2 litre engine which powered the B Type Connaught. Hugh Rose's Lea Francis engine appeared in the late 1930s and as you say was very similar to the Riley 12/4 which Rose also designed.

JH

Originally posted by Dutchy
Without wishing to detract from the validity of your point I should say that the Alta dohc engine has nothing whatever to do with the high camshaft Riley and Lea Francis engines. The Alta engine first appeared in 1928 in 1,100cc form and was gradually developed into the 2 1/2 litre engine which powered the B Type Connaught. Hugh Rose's Lea Francis engine appeared in the late 1930s and as you say was very similar to the Riley 12/4 which Rose also designed.

JH

I should have remembered that - we have a 2.5 liter Alta engine in our Connaught! Really could do with Duncan Ratbag finishing his Alta history!

Was it Turner who made Lea-Francis based engines in the 50's?

As you say the point is still valid - the Alta design was already old.

Peter

Jack Turner did build a F2 car with a Lea Francis engine which as far as I know would have been the same as the engine used in the Connaught A Type - I don't think the engine had any Turner input.
Incidentally the Lea Francis engine in it's standard 1,767cc configuration was also exported to America to be used in dirt track racing cars.

JH

A little more research suggests I might be incorrect in my previous post. It would seem that the engine in the Turner F2 was very similar but not identical to the engines used by Connaught. Jack Turner did build further Lea Francis based engines.

Incidentally my searches have led me to ask a question which I think merits a new thread.

JH

Just to confuse it all slightly I think I was originally thinking of the Lea-Francis based engines used by Connaught.
I'd assumed the A-types used Alta engines as did the B-types, but of course the sportscars used LeaF engines so I probably did know that the F2 cars weren't Alta.................

Lotus Mk VII Replica

This is taking quite a bit of time because we first had to completely dismantle the Clairmonte Special and make drawings of all the parts which it shared with the single seater. This included front wishbones, the king posts, wheel centres, the de Dion rear suspension, and the parts needed to convert a Halibrand Final Drive Unit to have inboard brakes and be fitted to the chassis instead of at the centre of a live axle.

The chassis frame is nearly complete as may be seen from the attached photos with the upper wishbones in position. I am taking the lower wishbones to be expertly welded this afternoon, and the next job is the jig for the de Dion tube.

This thread should, IMHO, continue under the original thread "Restoring the Clairmonte Special" and this is where I will continue my messages on this subject.





I would like to have talented artists give me their view of what the body should look like. I personally feel that the rear end would look very similar to that on the Lotus Mk III (narrower of course) and the front very similar to the Lotus Twelve, but without the wraparound windshield of the Twelve which resulted from ACBC's exposure to Frank Costin, which was two years after the Mk VII was designed.

By the way, the email address shown below is WRONG and shouild be peter@historiclotusregister.co.uk I have changed my profile but it has not changed the bit below that gets added auitomitically.

Body for Lotus Mk VII replica

This is a copy of what I wrote recently to someone who showed interest in helping to design a body for the single seat Lotus Mk VII.

“I was interested by you post regarding F1 body appearance. You are obviously a gifted artist with an eye for a good shape.

Would you like to design a body for a car that was intended to compete in the 1952 and 1952 F1 championship races, but was never completed?

As you may knew, in those years the Grands Prix were held using the F2 Formula of 2 litres unsupercharged and 750 cc supercharged (I don't think there were ever any of the latter).

In late 1951 Clive Clairmonte commissioned Colin Chapman to design him a F2 car to use the 2 litre Riley engine from his ex-Hector Dobbs Riley which he had been racing. Chapman accepted the commission and designed a car that he called the Lotus Mk VII. This car must not be confused with the 1957 Lotus Seven which was a completely different car.

Lotus started to build the car, but as they were also making the prototype Lotus Mk VI and there was only one full time employee (Michael Allen), progress was slow. They had not got further than making the chassis frame, the front suspension, and the engine mountings, when Clairmonte got fed up and took the car away to finish it himself. He had already missed the 1952 season.

The car's body had no doubt already been designed by Chapman, but no record exists of what it would have looked like. Clairmonte decided that one season (1953) in F2 was not going to be worth it, and changed the car into a two seater with a Lea Francis 1.5 litre (later a Connaught 2 litre) engine. He designed a body for it and the car was finished in 1953 and named the Clairmonte Special.

Clairmonte brought a legal action against Chapman for failing to pay back money he had paid for a complete car, and Chapman disowned the car and used the number again 5 years later.

I have bought the Clairmonte Special with a friend (Dr David Harvey) and we are restoring it to race in historic sports car races. More importantly we are re-creating Colin Chapman's first single seater. The chassis frame is nearly finished, the de Dion axle and Halibrand final drive are on the way, but we do not have a body design.

It was the first car that Chapman designed after the Mk VI and would, I think, have looked rather like a combination of this car, the earlier Lotus Mk III and the later Lotus Twelve.

You can see photos of all these cars on the Historic Lotus Register website http://www.historiclotusregister.co.uk, and I can send you more. I think it would be an interesting challenge to create a design that might have been Chapman's in 1952. I was there in 1952 when the car was being built.

I have attached various images.





The first two show the rear end of the Lotus Mk III which was designed in late 1950. There is a photograph and an original ACBC drawing of this. Although the single seater would have been narrower, I believe that the profile of the rear end would have been very much like this. The photo is from William Taylor’s “The Lotus Book” and shows the Lotus IIIb whose body was made by Williams & Pritchard. The first Mk III, the Lotus-Austin, had a body made by Frank Hine.



The next drawing is rather a precious one as it is the very FIRST that Colin Chapman did for his new Lotus Mk 12 in 1956 - just 5 years later. You will see that the rear end is very similar to the Mk III. I think the front of the Mk VII would have been similar to this shape as well. Please note that the Mk VII would NOT have had the wrap around windshield shown for the Type 12. That's something he learnt from Frank Costin whom he had not met in 1951. Keen eyed readers will note the de Dion suspension.



Finally there is an artist's impression of how the Lotus MK VII might have looked (just the sort of thing I am hoping you will do). He has got the details of the wheels and de Dion suspension correct, but the tail comes up too high behind the driver. There is something about it that does not feel quite right.



For more information on the car go to the HLR website and click on "the Cars" and then "Lotus Mk VII". For even more information you can look at http://www.simplesev...monte/index.htm
The story is covered in the greatest depth in the book "Lotus - The Early Years 1951-54" published by Coterie Press, where I have written a long account of the Clairmonte Special.”

Would Colin Chapmans body design have had such a power bulge for the engine ?

Doesn't it look a bit too low slung and ' modern'for the early 50s ? The nose cone a bit too small and low for the period

Doesn't it look a bit too long especially in the middle?

It would certainly have to have looked an earlier evolution than the 12, perhaps a bit more in the style of the GP cars of the time , but noticeably smaller in all dimensions ?

Lotus Mk VII Body Shape

I forgot to send the image of the Lotus Twelve Rear End in my last message - you must have wondered at my mention of the de Dion rear suspension on this first layout drawing by ACBC.




The large bulge in the bonnet is needed to clear the rocker covers on the Riley engine. If you look at photos of the Clairmonte Special on the HLR website (Click on "The Cars") you will see they had to do the same on that for the Connaught and Lea-Francis engines which owed a lot to the Riley design.

I think "Cuckoo Mills" just about sums it up !!!!!!!!!!!!!!!!!!!!!!!!!!!!!

The chassis of the replica seems to be brazed? I'm surprised to see this as other Lotus chassis of that date are gas fusion welded. Any reason for this?

The photos suggest that the tubes aren't quite parallel to each other and the brackets for the lower front wishbones remind me of Cooper construction.

I think that RTH asked for dimensions to assist the body designers. I think that the job is well nigh impossible without. Isn't there a tale about Chapman bringing another bare chassis round to Williams and Pritchard (who would presumably have put a body on the original single seater if it had got that far) and saying something like "come on lads, throw a body over this one". I do think you have to have the car built up with the wheels on and an engine in (or at least a drawing) before you can visualise the body shape.

Ted !

I'm sure you are right Charles about the fusion welding but as they all found out eventually , high temperature oxy acetylene fusion welding thin wall steel tubing stressed structures ends in cracks and fractures on the edge of the welds. Lower temperature Brazing,bronze brazing and eventually nickel bronze brazing are far far safer more durable and reliable.

We do know Colin Chapman's training made him keen on doing drawings simple 3rd angle projection technical drawings. There is a photo of him in the Allen home garage at a small drawing board , unheard of really for a special builder !

Keith Duckworth said in an interview Chapman would draw parts at home often for most of the night , working very quickly although Keith said the small detail was not always totally reliable the work rate was amazing and drawings were very important to him.

I feel sure he would have taken all the dimensions of the components to be used and fully drawn the car including the body shape which to a large extent would have been dictated by the height of the engine if only in profile and plan.

Of course we will never know what it would have looked like an amalgam of 3, 6, and 12 ?

The Lotus bit ends at the bare chassis point the customer took it away.

Certainly the photos on the HLR site of the chassis at the time it was being made do look quite unlike anything else the firm had done just before or just after and there is some light body framing already in place giving some indication as to the shape in the engine area at least .

Richard, I think this photo (linked from the HLR website) shows body framing for the two seater Clairmonte.


Photo courtesy of Zoe Calvert
It is followed by the text:
The Clairmonte Special nearing completion at Clairmonte's Shanklin Road factory, but before the Lea-Francis 1.5 litre engine was fitted. The inboard springs for the wishbone front suspension may be clearly seen

I'm interested to read what others think about the welding. I'd rather see something that accurately represents what was done at the time rather than an improved version. The welds on my 1952 Lotus chassis seem to be holding up OK (touch wood!)

Ah, right Charles I hadn't noticed that was two seater form, the height of the top of those rocker arms on droop and the height of the engine would have involved quite tall bodywork, and could not have been that narrow either.

Those lower wishbones look like oval tubing which only really came in to vogue in the 70s !

those very long springs would have made it quite softly sprung, yet the long canterlevers would at the same time controlled roll probably quite effectively. The sort of thing that was done much later to enable softer compound tyres to be utilised yet still last the race distance. Can't imagine you even had tyre compound options to any extent in the early 50s?

This is indeed quite a stange car for it's period.
Do we know how effective it was as a sportscar ?

Charles I suppose I should know , but which 1952 Lotus do you have ?

The Lotus is Mk6/3, Denis Wilkins car registered JZ 7890 in July 1953. The panelled chassis must have been built in 1952 as it appears in the Lotus advertisement in December 1952. The Consul engine mounts are clearly visible in the advertisement. Built up by Patrick Stephens for Denis on ACBC's recommendation. Denis worked with Colin at British Aluminium Company.

Patrick Stephens wrote this most brilliant book in 1953, I bought the fourth impression in 1961 at age 11 it really was my inspiration to get involved in motor racing.

Originally posted by Charles Helps
The Lotus is Mk6/3, Denis Wilkins car registered JZ 7890 in July 1953. The panelled chassis must have been built in 1952 as it appears in the Lotus advertisement in December 1952. The Consul engine mounts are clearly visible in the advertisement. Built up by Patrick Stephens for Denis on ACBC's recommendation. Denis worked with Colin at British Aluminium Company.

Interesting Charles do you have any photos ?

Many, Richard but I'll just post one as it is a bit OT!


Photo courtesy of Denis and Denise Wilkins

Denis Wilkins at Snetterton on 11th July 1953. There's a picture of the three Lotus 6 replicas on the same day in Peter Ross's Lotus The Early Years - of interest because the bodies are all different - partly because the engines fitted were blown MG J4 747 cc (Fred Hill's Empire Special), Ford Consul 1499 cc (Wilkins) and Nigel Allen's 1172 cc sidevalve Ford. I think you are buying the book which also has more details on the Clairmonte.

I must keep an eye out for a copy of the Patrick Stephens book on his 750 special - I've got his later one on Ford Specials .

The bodywork was so well crafted on those 50s Lotus', lovely car .

[QUOTE]Originally posted by Charles Helps

The chassis of the replica seems to be brazed? I'm surprised to see this as other Lotus chassis of that date are gas fusion welded. Any reason for this?

A very simple reason. I am building the chassis frame myself and do not have the skill to produce a neat fusion weld. My skill when bronze welding is considerably better (having built many recumbent tricycles using this method) and when painted the result will look the same.

Some fusion welding has to be carried out when the joints are in tension (such as the upper lengthwise tubes).

The photos suggest that the tubes aren't quite parallel to each other and the brackets for the lower front wishbones remind me of Cooper construction.

The photo was taken before all the tubes were finally welded into place.

The brackets are an exact copy of what were used on the original chassis which became the Clairmonte Special.

We have been looking for a manual gearbox to fit to the Riley 15/6 engine in the Lotus Mk VII replica. The Riley engine was normally fitted with a Wilson preselector gearbox made by Armstrong Siddeley, and whilst we went on looking for a manual box it was suggested that we fit a preselector box to get the car mobile.

We have been given a preselector gearbox, but it is not from a Riley. We would like to swap it for the correct gearbox but first need to identify from what car it would have come. Can anyone help?

http://img232.images...eywilsonyh6.jpg
http://img232.images...eywilsonen0.jpg
http://img234.images...ywilsongjg8.jpg
http://img232.images...eywilsonbg1.jpg

Wikipedia says: "They were common on Daimler, Alvis, Talbot-Lago, and Armstrong Siddeley cars as well as on many London buses. They have also been used in racing cars, such as the 1935 ERA R4D, and hillclimbing cars such as Auto Union "Silver Arrows". Military applications included tanks such as the German Tiger I and Tiger II in World War II, through to the current tanks such as Challenger 2."

In the photographs the interesting thing to note is that the input shaft is the propeller shaft, so the gearbox was mounted separately to the engine as well as separately to the rear (or front?) axle.

I feel that the most likely vehicle would have been some sort of Alvis armoured car, bit I am sure some knowledgeable person amongst you will be able to provide the correct answer.

Riley manual gearbox

We are still looking for a manual gearbox for the Lotus Mk VII replica. We have been told that any "silent third" manual gearbox from a Riley Six will do, and even a "silent third" box from a Riley Nine could be made to fit. Can anyone help or know someone who might?

In my last post I tried to include some images of the gearbox. Something seems to have changed on the imageshack website as all that has appeared are some website addresses. I have tried again with one of them, and if this comes out OK I will add the others.

[URL=http://imageshack.us][IMG]http://img232.images...eywilsonbg1.jpg[/[/IMG]

Peter, if you go down to the second group of address links on the imageshack site (scroll down) and select the first choice there it should work ok for you.