“”Lotus really came of age in 1954 with the beautifully streamlined Mk.8”
The editors interest in and canvassing for the proposed Colin Chapman Museum and Education Centre is based on the fact Chapman possessed a commanding intellect, combined with a force of imagination, innovation and determination.
These he harnessed and marshalled to solve engineering and strategic problems.
We believe even if Chapman had possessed greater capital he would still focus his brain in an intellectual guerrilla manner to overcome obstacles.
These skills and aptitudes had already been demonstrated by the time he conceived the Mk.VIII. However at 26 years of age he displayed an enormous maturity and again proved and produced the revolutionary Mk.VIII –possibly the most scientifically and sophisticated sports racing car of the era.
This article is therefore very much about the concept, origins, design, execution, management and evaluation of the Mk.VIII.
We provide details of race entry for the exclusive purpose of benchmarking contemporary competition by marque.
There is no doubt in the editor’s mind how gifted Chapman was. The essential lesson he presents is that intelligence, ingenuity and creativity are the foremost tools of problem solving.
We believe this remains as relevant today as in his era.
As such we believe his legacy informs and can inspire today and tomorrow.
Subscribers might like to see directly related A&R articles:-
- MG engines
- British Aviation and examples of aircraft design
Particularly relevant reading for this subject are:-
- Colin Chapman.Ludvigsen
- Racing and Sports car chassis design.Costin&Phipps
- Lotus: The Early Years. Ross
Chapman, Triangulation and Congruent Triangles
Chapman is perhaps too often stereotyped as the structural engineer.
Yes he adopted the principles of triangulation to produce reinforced light weight chassis, however the editors see convincing evidence that the holistic Chapman maintained a design philosophy and management style that resembles the congruent triangle.
His most effective cars were a balance of three integrated forces:-
- His personality, motivational , magnetism , determination and innovation, improvisation driven mind
- The use of materials and mutation of suitable existing components or resources to his purpose ;often improved and given added value along the way
- Chapman the purest engineer/scientist could converse with others of like mind. He could respect their ability, assess the contribution they could add or complement his own. Possibly most important others saw in Chapman a person who’s determination would act as facilitator and where their ideas had been overlooked could find recognition , expression concrete execution and evidence of correctness
These qualities we see played on various occasions. Although it must be considered that Chapman might on occasions have been slightly exploitive of others and not always giving due credit.
The early examples are:-
- The Allen brothers
- The “DeHavilland” Team including late P.Ross and Gilbert [Mac]Mackintosh
- Frank and Mike Costin [see below for Franks major contribution to the Mk.VIII body shape]
- Keith Duckwoth
- Ron Hickman
- Len Terry
- Exceptional artisan craftsmen like Progress Chassis [Dave Kelsey and John Teychenne and Williams & Pritchard
His professional colleagues in many respects, but not all, had a similar angle of approach and attack.
In future articles we will develop this and expand on others who supported Chapman
[Subscribers are directed to Taylor The Lotus Book for an extended comprehensive listing of those concerned.
Brief Historical Background /Context
“during the winter of 1953 ,Colin Chapman put pencil to paper and devised a chassis for a new car based on the theory of structural strength through triangulation.to go with this chassis Chapman wanted a more streamlined body ………….”
“During 1953 the 1500 cc sports car racing class had attracted a great deal of attention from manufacturers which resulted in very closely fought , fast racing .It was this class that Colin wished to design a car………………..the opposition was stiff and a variety of sports racing cars were appearing in the class from Connaught ,Cooper, Leonard and Tojeiro.The masters in this particular field were the Porsches .In order that Lotus should stand a chance against this machinery –and Colin included the Germans in his recognising –some sort of “march must be stolen”
Chapman wished to move up in prestige racing and this meant competing with the “establishment”. In the Lotus Story Part 4, Colin Chapman stated:-
“After three years in several classes of racing, I started to think about a car for 1954. The new car would need to be as far ahead of other competition cars in its class as the Mk. VI was when it emerged in 1951.
This was the ever-present problem-always keep one or two steps ahead of the competitors. People ask me why I don’t give up racing and concentrate on design-the answer to that is that I must race the cars myself to find out design faults. Drivers are always a bit vague about handling and similar details, so the only thing to do is to find out things myself……………
It seemed to me that an efficient aerodynamic body would be the thing to have for the 1954 season………..”
Peers and Contemporaries
It’s important to study these as Chapman might. He would probably conduct an analysis of strengths and weaknesses and decided how best he might improve on existing best.
Equally significant is the fact that Chapman was a realist. Budget and engine availability would focus his mind on the alternative methods to beat the competition.
- Nb see appendix below for fuller cross section of marques as represented by entrants at 1954 Empire Trophy, Oulton Park.
Factors determining the specification of the Mk.VIII
Harvey identifies three main parameters:-
- Aircraft aerodynamic principles
- Porsche adoption of low drag bodies
- Banning of cycle wings in International racing
He therefore deducts:-
“Colin had to go for a full width body if he wanted to compete among the top echelons”
It’s worth noting that the aerodynamic body had both advantages and disadvantages.
The extra weight would have to be compensated for elsewhere forcing considerations of the chassis and main mechanical components like the engine.
Outline the specification of the Mk.VIII
It’s believed that Colin set the guiding parameters of his concept as:-
- Top speed in region 120-125 mph deducted from linked factors/components /data
- 85bhp engine output
- Weight in region of 1000lb
Chapman, Necessity and Design Methodology
“What set Colin apart from other contemporary racing car designers was his very practical approach .This was in part dictated by his almost total lack of working capital, which meant that he always had to have something in current production to generate cash flow, and whatever he made himself ………….to race had to be capable of being rapidly turned into a production vechicle to sell to paying customers ……….
Whilst other companies could afford to start with a blank sheet of paper, Colin’s first thought was “what existing part can be used or what existing part can I adapt to do what I want ……………”
Lotus were not an engine manufacturer until late on in their history. Our appreciation of Chapman’s achievements must take this fact into account.
Chapman had to work with what was available and affordable.
He had to work within these constraints.
It’s necessary to have a brief analysis of the implications.
Subscribers might like to see A&R articles on the 1172 and 750 Formula’s and Lotus Power Plants.
Most mass production car manufacturers make their own engines. The size and performance of those engines are determined by considerations such as:-
- Market requirements primarily user categories
- Weight and physical size/ volume
- Fuel economy
- Legislation regarding taxation and insurance categories etc.
- Peer competition
- Economies of scale and families of product offering interchangeability etc.
- A lesser consideration might be aesthetics , aural and visual
- Some manufacturers might consciously enter competition and develop products expressly for this
However they rarely make dedicated competition engines. This was a rub. Chapman had to extract from what was available and cost effective.
Some of the most used engines in the specialist sports car sector are:-
- Austin Seven  plus A30/A35 etc.
- Ford 1172
- Ford Cosworth
- Ford crossflow
- Ford V8
- Jaguar XK engine series
- Coventry Climax [nb this type FWA used in Mk.VIII]
- Recently motor cycle engines
- 2L Bristol
- 5L Connaught
- Turner [a period engine of 1.5L fuel injected is reputed to have produced 110bhp.
[See our dedicated articles for bhp analysis .A tabulation of common mass produced engines is included in our article on MG engines used by Lotus]
Racing classes on occasions deliberately coincide with industry trends but this has never been perfect. Specialist manufacturers have sometimes been at a disadvantage regarding choice and performance. However as in Chapman case this has been the mother of invention.
When considering the 1500 racing category Chapman had to decide which engine would be within the class limits, be available, affordable, and possibly capable of being improved cost effectively and probably physically able to fit.
A Lotus Mk.VI registration no.UPE 9 had dome extraordinarily well in club racing c 1954 [the editors believe it won something like 14 races out of 17?] This car had a gifted driver and many other unique parts and mofifications.But the MG engine had demonstrated its potential.
It’s probably this specification of engine that Chapman elected to go for in the Mk.VIII
M.G. Engine Summary Details
Here will deliberately only provide bullet summary. The MG engine discussed is worthy of full dedicated article as it powered MkVI and MkVIII.Please see this item that also records the MG gearbox and tuning upgrades etc.
- MG/Morris based XPAG
- Claimed 85bhp at 6,200rpm
- Laystall Lucas alloy head and other Laystall modifications
- Bored out to 1467cc
- Twin SU carburetters
- Costin&Phipps suggest engine weight at 228lb , gearbox 32lb
The claimed output of 85bhp ought to be noted. The standard engines were quoted in the mid 50 bhp range. Peter Gammon achieved some remarkable successes in Mk.VI [UPE 9] .It has to be questioned what was done to the engine and if independent dyno meter tests could confirm .The extraction of 85bhp was an achievement.
MG had been record breaking and it’s possible they developed some modifications that were not available on production cars.
Chapman would have calculated both the power output of the engine, chassis and rolling chassis. It’s from this data he probably realized that an extremely efficient and aerodynamic body was required to provide a chance of winning.
Right from the outset it’s important to state two very different chassis types were used in the 7 Mk.VIII produced.Costin &Phipps perhaps providing the best technical analysis.
- SAR5 –first road registered 27th March 1954
This was an extraordinarily sophisticated chassis for the era. Chapman went to great lengths to reduce weight in order to possibly compensate for the engine output. Subscribers are directed to the full and comprehensive technical description of this chassis provided by Costin and Phipps who had close firsthand experience. Here we summarise and paraphrase .Our model with mannequin is based on this first concept.
“The Lotus Mk.VIII structurally , the most nearly perfect sports car chassis yet made ………..very simple extremely light yet very stiff ,this chassis the only one of its type ever made –is still giving good service after six years of use ,and this despite the fact it is made up of 20and 18 gauge tube…………”
The editors find in strange that most accounts explain this chassis caused problem for the mechanics regarding engine servicing .Access is importance when racing ,particularly if a highly stressed engine is to be kept in tune. If Chapman was aware of this, and as we believe using not a fully ideal engine he might have been more generous in space allowance.
We suggest the following might have occurred:-
- That Chapman took dimensions for a standard engine from drawings. That these varied from engine eventually used
- That Chapman used an existing engine to dictate chassis layout ,then discovered the commissioned engine was at variance ,possibly as result of tuning
- That a genuine mistake occurred in measuring, drawing or translation into reality or that to meet other strict structural criteria the engine bay became sacrificial to overall concept
- That the all-enveloping body once fitted so ensconced the engine that access was reduced to impracticality
Figure 2.Editors model of the basic stage chassis with artist’s mannequin to indicate approximate scale. Model made from drawings.
Ross provides some insights into this anomaly.
Taylor comments that the chassis was of steel tubes of 1.25 inch 20swg.It reputedly weighed 35lb? Whereas Costin &Phipps suggest:-
“Only 19 members are used in its construction, and the total weight is 21 lb. al lmembers are straight and there are no structural offsets”
- B) “Production Mk.VIII- Modified from Mk.VI
“After the start of the 1954 season a number of privateers began demanding Mk.VIII… the “production ”Mk.VIII differed from the prototype in many ways ,not least the chassis design ,in order to ease the maintenance problems associated with SAR 5 ,Chapman reverted to the earlier Mk.VI chassis with several important differences …………….”
The alternative and possibly more practical chassis for the Mk.IX was a version of the Lotus Mk.VI and weighed 75lb.
Technical Specification from Taylor
|Carburation||Twin H6 S.U.|
|Power Output||85 bhp|
|Chassis||Tubular steel space frame|
|Front Suspension||Split swing axle with cs dampers|
|Rear Suspension||de Dion axle with transverse cs piston dampers|
|Brakes F/R||Lockheed 9x 1.75 Alfin drums , [inboard at rear]|
|Wheels F/R||15 inch 40 spoke wires|
|Tyres F/R||4.50 x 25 and 5.25 x 15|
|Height||32 inches to scuttle|
Mk.VIII Registration No.
Although Taylor quotes a production volume of 7 cars photographic and other sources suggest that the following might be included:-
Form, Function and Flight Tested by Frank Costin
“The body was developed by Mike Costin’s brother, Frank……at de Havilland .Frank had no experience of car design, but realized that the potentially high top speed and light weight of the car would require a high degree of straight line stability……….he produced an exceptionally graceful and low body design with extended front wings tapering to points, the passenger side of the cockpit fully enclosed by metal tonneau, spats over the rear wheels and twin tail fins”
Figure 3.Editors drawing of the chassis and Mk.VIII in side elevation [relate drawing to model to better comprehend form function]
Typical of the era Frank Costin allowed himself to be strapped to the car and driven at high speed in order he could personally observe air flow/ stream .the tests at a disused airfield [see photo reference in most textbooks ] were conducted at about 100mph.
The significance of which is to forgo personal safety in order to establish his design correctness. It’s also a measure of confidence and commitment to get the best possible.
This behavior was that of the boffins of the era.
Subscribers wishing to comprehend the sophisticated body shape of the Mk.VIII might like to obtain scale models by the likes of Merrymeet and Midlantic.The editors believe these are in the small scale of 1/43rd.
Figure 4.Lotus Mk.VIII [SAR5] features on cover of Unique Books
The complex body comprising double curvature was executed by Williams &Pritchard.
“the body shell was built of 20swg alloy….only the front section of the bodywork was removable ,the remainder being riveted to the supporting sheet alloy and chassis tubes…..the “production bodies were built of 18g alloy and were similar to the prototype but without the rear air outlet in the boot lid”
The editors have not been able to discover the man hours required to construct the complex body shape. However we have extrapolated for other data that it might be approximately 40-45% of the cost.
RAC British GP, Silverstone.1954, Racing Sports cars. [Peers]
The editors publish this information from the net to:-
- Allow subscribers to research other marques of the era
- To forensically analysis the Mk.VIII performance against this opposition factoring in elements like budget, engine performance, weight etc.
|2||Kieft||LDA 1||Climax||FWA||1100 cc|
|4||Lotus Mark VI|
|7||Osca MT4||1134||MO24307||Osca||no:1123||1100 cc||L4||N/A|
|9||Porsche 550||09||Porsche||1100 cc||F4 2v DOHC||N/A|
|10||Lotus Mark VIII||MG|
|11||Lotus Mark VIII||8/01||SAR 5||MG||1500 cc||L4|
|12||Lotus Mark VI||UPE9||MG||1500 cc||L4|
|13||Lotus Mark VI||NUF 100||MG|
|14||Connaught ALSR||12||MCA 200||Lea Francis||1500 cc||L4||N/A|
|15||Lotus Mark VIII||Connaught||1500 cc||L4|
|16||Cooper Disco Volante||Connaught||1500 cc||L4|
|18||Gordini T15S||0018S||Gordini||1500 cc||L4|
|20||Killeen K1||K1||MG||XPAG||1500 cc||L4|
|21||MG TD Special||MG|
|29||Lester T51||MG 6850||MG|
|30||Osca MT4||Osca||1350 cc||L4||N/A|
|33||Porsche 550||Porsche||1500 cc||F4 2v DOHC||N/A|
Entered cars that did not arrive:
|Overall:||11||Lotus Mark VIII MG||Colin Chapman|
|Sports 1100:||9||Porsche 550||Huschke von Hanstein|
|Overall:||12||Lotus Mark VI MG||Peter Gammon (GB)||2:05.000||135.667 km/h|
|:||33||Porsche 550||Hans Herrmann (D)||2:05.000||135.667 km/h|
|Overall:||33||Porsche 550||Hans Herrmann||2:17.000|
|Sports 1100:||7||Osca MT4 1100||Jackie Reece||2:23.000|
|Notes of interest:|
|Top makes by numbers:||Lotus (6), MG (4), Porsche (2), Cooper (2), Osca (2), Tojeiro (2), Kieft (2)|
|Top engines by numbers:||MG (16), Porsche (2), Connaught (2), Osca (2), Climax (2)|
|Top car types by numbers:||Lotus Mark VIII (3), Lotus Mark VI (3), Porsche 550 (2), Osca MT4 (2)|
|Driver nationalities:||GB (25), D (2)|
|Oldest known drivers:||Huschke von Hanstein (43), Ken McAlpine (34), John Riseley-Pritchard (30)|
|Youngest known drivers:||Brian Naylor (-5), Hans Herrmann (16), Archie Scott-Brown (17)|
Taylor observes “the crowning glory of all Mk.VIII races was at the British GP meeting at Silverstone, Colin Chapman had the satisfaction of winning the supporting 150cc race in his own car beating Gammon’s mk.VI and Hermann’s works Porsche………..”
A Perspective on Performance
Tipler quotes John Bolster who road tested a modified Mk.VIII in 1954 with the following results:-
0-60mph 8 sec
0-100mph 23.8 sec
Retail Price and Cost comparisons
Ross draws a parallel with Connaught and quotes Dave Kelsey:-
“at the time I was building single-handedly one Lotus chassis a week and we were getting about £50 for it .Connaught told me their streamliner single seater, which they proudly unveiled for me, cost £10,000] and took nine months to build ……….”
The editors have seen other prices suggesting the Mk.IX with Coventry Climax engine was offered at £1,150 complete plus Purchase Tax or without engine at £800.
This was of course expensive. See our complementary articles with reference to relative income costs etc. [recent example in discussion Seven S1]
Our learning /educational opportunities are intended to be challenging thought provoking and requiring additional research and/or analysis.
These opportunities are particularly designed for a museum/education centre location where visitors would be able to enjoy access to all the structured resources available in conjunction with any concurrent exhibition.
In this instance we suggest the following might be appropriate:-
- Study interrelationship between Aerodynamics, efficiency ,sustainability
- Make Performance calculations –speed ,weight, aerodynamic drag
- Compare /contrast cd of modern cars with Mk.VIII
- What was contribution of MG engine to Mk.VIII package?
- Why do you think only seven Mk.VIII were sold?
Exhibitions, Education and Economics
In the museum context the editors believe that commercial considerations are both necessary and complementary with its educational objectives.
For these reasons our suggested outline Business Plan includes provision for promoting products and services which share Chapman’s ideals of mechanical efficiency and sustainability. In addition we propose merchandising that explain and interprets the social and cultural context of Chapman’s designs in period. It’s suggested there will be catalogue for on line purchasing.
In this instance we consider the following exhibitions appropriate:-
- Flying Finns
- Pieces of Eight
- Flight and Slight: Chapman outmaneuvers with Mk.VIII
- Take Flight: The Lotus Mk.VIII
- Travel by Air: The Lotus Mk.VIII
- Wind Borne: The Lotus Mk.VIII and 1950’s aerodynamic sports racing cars
- Fight Tested
- Eight Days a Week
Capels observation of the Mk.VIII:-
“Although the Lotus Mk.VIII undoubtedly established Lotus as an international sports car manufacturer only 7 were built in 1954 –early 1955.
Progress at Lotus was never slow”
The Lotus Mk.III took off from Hornsey and required a massive leap of imagination, courage and confidence into the future.
Chapman was decisive and we feel we can summarizing his achievements with the Mk.VIII in bullet form. It’s worth noting the skills demonstrated here were practiced into the future:-
- It was measure of Chapmans maturity both in his age and that of his young company to attempt something so ambitious
- It shows how Chapman was able to use experts. He was able to comprehend theoretical concepts and practice these himself. He was a consummate facilitator and animator
- At this stage Chapman was still driving competitively providing feedback and establishing brand reputation
- The competition success of the Mk.VIII established Chapman and Lotus on the International stage
- Competition success garnered commercial success in sales whilst enhancing the British specialist and engineering economy
- Chapman in the first instance is the purest but he was also realistic and modified designs for commercial advantage
- In the Mk.VIII Chapman enters a theoretical, objective and scientific design approach. This was evident elsewhere in British aeronautical circles including jets. This would never leave Chapman.
The appliance of science was gift of Chapman and along with the other skills including that of driver made him an extraordinary holistic design engineer.
Chapman’s facilitating, animating skill and intellectual rigour is to be learnt and applied. It’s an inspiration and proves as relevant now as in the 1950’s
The Mk.VIII were built at Tottenham Lane, Honsey, London N8.
Appendix 1. Competitors and Entrants, 1954 Empire Trophy, Oulton Park
|1st||28||Alan Brown||Cooper T20 Sports Bristol||Bob Chase||32||59:03.000||115.872 kms||113.155||1st||S2.7|
|2nd||35||Roy Salvadori||Maserati A6GCS||Gilbey Engineering||32||59:37.000||2nd||S2.7|
|3rd||11||Peter Gammon||Lotus Mark VI MG||Team Lotus||32||59:41.900||1st||S1.5|
|4th||45||Duncan Hamilton||Jaguar C-type||Duncan Hamilton||32||59:54.000||1st||S+2.7|
|5th||52||Sanderson||Jaguar C-type||Ecurie Ecosse||32||59:55.900||2nd||S+2.7|
|6th||51||Jimmy Stewart||Jaguar C-type||Ecurie Ecosse||32||59:56.000||3rd||S+2.7|
|7th||36||Cliff Davis||Tojeiro – Bristol||F. C. Davis||32||1:00:11.000||3rd||S2.7|
|8th||43||George Abecassis||HWM Jaguar||HWM||32||1:00:15.000||4th||S+2.7|
|9th||29||Bob Gerard||Frazer Nash||F. R. Gerard||32||1:00:20.000||4th||S2.7|
|10th||1||John Coombs||Connaught ALSR||John Coombs||31||59:20.000||2nd||S1.5|
|11th||32||Peter Scott-Russell||Frazer Nash||P. Scott Russell||31||59:44.000||5th||S2.7|
|12th||46||Joe Kelly||Jaguar C-type||J. Kelly||31||1:00:11.000||5th||S+2.7|
|13th||17||Chris Threlfall||Turner||C. H. Threlfall||31||1:00:52.000||3rd||S1.5|
|14th||5||Redmond Gallagher||Gordini T15S 1.5||R. Gallagher||30||59:18.000||4th||S1.5|
|15th||54||Berwyn Baxter||Jaguar C-type||B. Baxter||30||1:00:10.000||6th||S+2.7|
|16th||15||Ted Lund||MG TF||T. Lund||30||1:00:14.000||5th||S1.5|
|17th||27||Tony Crook||Cooper T24 Bristol||T. A. D. Crook||6||1:00:01.000||6th||S2.7|
Did not finish:
|30||Peter Reece||Frazer Nash||P. Reece||DNF||S2.7|
|10||Gerry Ruddock||Lester T51 MG||G. Ruddock||DNF||S1.5|
|7||Stirling Moss||Leonard – MG||Lionel Leonard||11||Crankshaft||S1.5|
|40||Beauman||Aston Martin DB3||Sir J. Boles||0||Brakes||S+2.7|
Did not start:
|50||Ninian Sanderson||Jaguar C-type||Ecurie Ecosse||S+2.7|
Did not qualify:
|49||Gerry Dunham||Jaguar C-type||Ecurie Kenya||S+2.7|
|4||John Riseley-Pritchard||Cooper Disco Volante Connaught||Cornhill Racing Team||S1.5|
|22||Ron Flockhart||Austin-Healey 100||R. Flockhart||S2.7|
|31||Dickie Stoop||Frazer Nash Sebring||R. Stoop||S2.7|
|34||Horace Gould||Kieft – Bristol||Gould||S2.7|
|48||Michael Head||Jaguar C-type||M. Head||S+2.7|
|55||David Boston||RGS Atalanta||D. Boston||S+2.7|
|53||Bob Berry||Jaguar XK120||R. E. Berry||S+2.7|
|25||Peter Kenneth||Cooper – Bristol||P. Kenneth||S2.7|
|3||Peter Jackson||Cooper – MG||Ec. North West||S1.5|
|16||Allan Moore||Tojeiro – MG||O Issard Davies||S1.5|
|21||Lance Macklin||Austin-Healey 100||L. Macklin||S2.7|
|37||Desmond Titterington||Triumph TR2||Titterington||S2.7|
|6||Leslie Jones||Kieft – MG||Ecurie Bullfrog||S1.5|
|12||Colin Chapman||Lotus Mark VIII MG||Team Lotus||S1.5|
|24||Frank Defty||Aston Martin DB2/4||Defty||S2.7|
|20||Alfred Hitchings||Austin-Healey 100||Ecurie Bullfrog||S2.7|
|9||Wharton||Lister – MG||G. Lister & Sons||S1.5|
|13||Mike Anthony||Lotus Mark VI||Team Lotus||S1.5|
Entered cars that did not arrive:
|2||Ken McAlpine||Connaught ALSR||McAlpine||S1.5|
|8||Brandon / Leonard||Leonard – MG||Leonard||S1.5|
|14||Tom Dargue||MG Special||T. Dargue||S1.5|
|23||John Dalton||Austin-Healey 100||Dalton||S2.7|
|26||Bert Rogers||Cooper – Bristol||Rogers||S2.7|
|33||D. E. Howard||HWM Alta||Howard||S2.7|
|41||Phil Scragg||Alta Jaguar||P. Scragg||S+2.7|
|42||Tony Page||HWM Cadillac||R. A. Page||S+2.7|
|44||Oscar Moore||HWM Jaguar||O. Moore||S+2.7|
|47||John Buncombe||Jaguar||J. Buncombe||S+2.7|
|56||Tommy Sopwith||Sphinx||Equipe Endeavour||S+2.7|
Appendix 2: Porsche 550 –c 1954 data from internet]
|Design||4 cylinder air cooled horizontal opposed 4 overhead camshafts|
|Power||Approximately 110ps (81 kW) at 6200rpm|
|Piston displacement||1498cc (91.4cu in)|
|Cylinders||Aluminium hard chromed walls|
|Valves per cylinder||An intake and an exhaust|
|Valve operation||2 camshafts per head driven by vertical shafts|
|Crankshaft||Full roller bearing and built up|
|Air blower drive||V-belt and crankshaft to generator shaft|
|Crankshaft to blower ratio||1:1|
|Air volume||1100ls at 6200rpm|
|Lubrication||Dry sump with oil cooler and filter in main current|
|Sparkplugs||Temperature valve 260-80|
|Carburettors||Solex 40 PJJ or Weber 40 DCM|
|Muffler||2 of them leading to an exhaust pipe|
|Clutch||Fichtel & Sachs K12 Porsche Special|
|Transmission||4 forward speeds, helical gears, synchronised, 1 reverse|
|Rear axle||Spiral level pinion, 2F lock tyre differential|
|Top speed||Approximately 140mph (220kmh)|
|Frame||Seamless steel tubing|
|Front springs||2 transverse, 4-leaf adjustable torsion bars|
|Rear springs||A round torsion bar on both sides|
|Shock absorbers||Fichtel & Sachs, telescopic hydraulic|
|Operation brakes||Oil hydraulic foot brakes to all 4 wheels|
|Brake drums||11.0236in (280mm)|
|Wheel base||83in (2100mm)|
|Front tread||50in (1290mm)|
|Rear tread||49in (1250mm)|
|Overall length||11ft 9in (3600mm)|
|Overall width||5ft !in (1550mm)|
|Unloaded height||3ft 4in (1015mm)|
|Minimum ground clearance||Approximately 6in (150mm)|
|Minimum turning circle||Approximately 36ft (11m)|
|Dry weight||Approximately 1300b (590kg)|
|Empty weight (DIN)||Approximately 1510lb (685kg)|
|Service weight (FIA)||Approximately 1410lb (640kg)|
|Axle weight||992lb (450kg)|
|Permissible total weight||Approximately 1984b (900kg)|
Lotus: The First Ten Years.Smith.MRP.1958
Racing and Sports Car Chassis Design.Costin&Phipps.Batsford.1974
Lotus Sports Racers.Capel&Clark.Brooklands.
Lotus. The Early Years.Ross.Coterie.
Lotus Sports Racers. Unique. [The Lotus Story Part 4]
Lotus Racing Cars.Tipler.Sutton.2001.
Please note the editors of the A&R attempt to give the broadest spectrum of references but not all are available for consultation in an article. However by noting their existence it may assist students in their research.
*Items in italics non A&R library books.