Aston Martin MKIII - Aston Workshop Book by Aston Workshop

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Restoration of the classic Aston Martin

DB2/4 Mk III

AM/300/3/1815

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CONTENTS CHAPTER ONE The History of Aston Martin

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CHAPTER ONE

DIARY DETAILS FROM RON POWELL

Origins The Interwar Years Enter David Brown Lagonda Motors The Post War Years up to 1971 Change of Ownership Aston Martin in Competition

CHAPTER TWO

APPENDIX A

The DB2/4 MkIII - A Car for All Time

The Post War Models up to 1964

Development History

The DB1

Chassis Development

The DB2

Suspension

The DB2/4

Engine and Transmission Developments

DB2/4 MkIII

Gearbox

DB 4 DB5

Braking System Other DB2 Developments The DB2 / 4 The DB MKIII

APPENDIX B Letters Etc.

The DB MKIII Engine Redesign The Updated DB MKIII Body

APPENDIX C

The DB MKIII Chassis and Suspension Changes

Restoration Notes

CHAPTER THREE History and Restoration of a DB 2/4 MK III Early Restoration Major Bodywork New Owner

The History of Aston Martin

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ORIGINS

he History of Aston Martin is a long and convoluted one is not untypical of much of the early and mid 20th century of British sports car manufacturing. Like so many of the illustrious names of British motoring history, this was a car company formed initially to enable a select group of wealthy individuals to go racing and hill climbing.

The start of what became Aston Martin was the occasion in early May 1914, when a certain Lionel Martin ascended the hill climb at Aston Clinton in a specially tuned Singer 10 and winning his class on handicap. By then he had resolved that he wanted to start manufacturing light sporting cars for the wealthy sportsman. Supposedly he drew a connection between his own name and the hill climb at which he came to prominence. This we presume led him to naming his cars Aston Martin.

THE INTERWAR YEARS

n 1920, Lionel Martin revived the business and restarted design and development of his car, beginning with the design and manufacture of their own chassis. The Coventry Simplex engine, which they had used in 1912, was heavily modified and tuned. Bodies were designed and built in house as simple open sporting cars, with minimal weather protection. By 1925 some 23 examples had been completed. There were 3 further development cars built, each being optimised for competition: the last one, named “Bunny”, successfully breaking the hill record at Brooklands in 1922. In 1921, Robert Bamford withdrew from Bamford and Martin, his place as director being taken by Lionel Martin’s wife, Katherine. As development costs mounted, it became necessary for Lionel Martin to find sponsorship to allow him to continue development and production. In this he was successful and shortly after in 1922, he obtained £10,000 sponsorship from Count Zborowski, who commissioned him to create

Lionel Martin was the son of a wealthy family with business in granite quarries in Lincolnshire. He was already

a racing car, powered by a twin overhead camshaft engine, to be entered for the 1922 French Grand Prix.

a partner in an established company, Bamford and Martin, a garage in London, which he founded with his

Two cars were built for this race and neither finished. By 1924, his company had absorbed £100,000, and it

good friend Robert Bamford in 1912. They had taken on an agency for Singer cars, with the intent to tune

became essential that further capital be obtained if development and production were to continue. Again,

and modify them for sporting use. With a colleague and mechanic Jack Addis, they had formed a successful

Lionel Martin was successful and in 1924, he had invited the son of Lord and Lady Charnwood, the Hon

partnership in developing the Singer 10 into a competitive light car,capable of over 70 mph. Other motor sport

John Benson, to join Bamford and Martin as director. This led to access to further finance, but for this,

enthusiasts soon asked for replicas of his own car, following the success he was enjoying. Encouraged by this

John Benson was given the lead in designing and developing another all new, twin overhead camshaft-racing

he and his business partner Robert Bamford decided to go into car manufacture; a decision taken

engine; a costly project. They exhibited at the 1925 Olympia Motor Show, but within a few weeks of the

following his success at the Aston Clinton hill climb.

show closing, the firm was put into receivership and Lionel Martin was asked to withdraw from the company.

Rather than continue in modifying and tuning Singer 10 cars, Lionel Martin decided that they should create

Lord Charnwood then bought the physical assets of Aston Martin and the company was put up for sale. It

their own design, using a proprietary 1400 cc Coventry Simplex engine. Impatient to make an early start,

generated great interest, including the Vauxhall Motor Company. The company was bought soon after,

they adapted an Isotta Fraschini Voiturette chassis; a car already with a successful sporting pedigree. The

however, by Mr William Summerville Renwick who then merged it with his firm Renwick and Bertelli, the

prototype was ready in August 1914 and was entered in the Brighton Speed trials. Shortly after, World

shareholding then being split 50-50 with Lord Charnwood to form Aston Martin Motors.

War 1 commenced, thus bringing an immediate halt to any further activities. Renwick and Bertelli was formed originally to design, build and manufacture high efficiency small engines for sporting use, which could then be sold to the motor industry. The initial design was based on an overhead camshaft 4 cylinder 1.5 litre engine of quite advanced concept for its day, leading to a significantly higher power to weight ratio than contemporary side valve engines commonly available. The development led to an approach from John Benson, leading, as indicated, to the merging of their respective interests to form Aston Martin Motors in late 1925. The new company brought in Augustus Bertelli, who was responsible for the design of every Aston Martin model up to the outbreak of war in 1939. In forming the new company, new premises were required and so Aston Martin moved from central London to Feltham, until eventually the site was closed in 1960. The initial car design produced by Aston Martin Motors was a 1.5 litre light sporting car, based on the Bertelli engine. It was low, fast and with excellent handling, quickly establishing itself as a very capable sporting car. A company formed by the brother of Augustus Bertelli, Enrico, was commissioned to provide the bodies. These were manufactured on an adjacent site, and being of excellent quality, added to the car’s reputation for high quality, though they were expensive.

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THE INTERWAR YEARS

Shortly after production commenced in 1927, the British and World economies were plunged into recession and with a general downturn in demand credit was tight and expensive and it became clear that there was a need to re-capitalise the company and reform it. By 1929, the company was very vulnerable and it was to continue in such a state until eventually being bought by Mr Arthur Munroe Sutherland, who, being a wealthy shipping magnate from Newcastle, put in his son, Mr Robert Gordon Sutherland, as joint managing director with Augustus Bertelli. These two continued to drive the company until 1947, when Mr David Brown bought the company. The new company was called Aston Martin Ltd. Models produced from 1929 until the outbreak of war, were all based on the original concept of a light chassis and sporting body using a small capacity, high efficiency 1.5 litre engine. This later grew to 2 litres with the introduction of the 2-litre model in 1936.

Aston Martin Team cars circa 1935 - Aston Martin enjoyed a successful competition history during the 1930’s, often winning their class in many prestigious races of the era, including Le Mans. The cars quickly established themselves on the race track at Brooklands, Le Mans and elsewhere, and their success only added to their reputation. Based on their Le Mans success, other events led to special sporting bodies, including a particularly elegant design first used at Dundrod in Ulster. This became known as the “Ulster”. In 1936, the 2 litre model was added. In common with other contemporary cars of the period, the fashion called for increasing comfort and sophistication. Weight under these demands, increased substantially. To compensate for this, it became imperative to increase power, thus creating the need for an increase in engine size to 2 litres. Complementing the engine, the Cotal electric pre-selector gearbox became a standard fitment. The 15/98 as it was known, was produced in three main versions, Saloon, Tourer and Drop Head Coupe. While the Tourer at least retained some sporting pretensions, the Drop Head and Saloon were heavy and rather under powered, but beautifully constructed. The initial 1.5 litre International model established Aston Martin firmly as a manufacturer of very high quality,

On the departure of Augustus Bertelli in 1939, Claude Hill was appointed as chief designer. Claude Hill’s

high performance sports cars, which could with equal felicity, be used on the race track and road. They were

first task was to design a replacement for the 1.5 litre engine used in the International. The 4 cylinder design

eminently practical road going cars.

configuration chosen maintained the overhead valves, but they were pushrod operated, using a clever system not unlike that used in the Riley car. This enabled the use of a wedge shaped combustion chamber and cross flow,with induction and exhaust being on opposite sides of the engine. The result was a very respectable power output with commendable fuel efficiency. To complement this new engine, Claude Hill also set out to design a new car. The new chassis introduced trailing arm front suspension and the use of a rigid rear axle located by twin trailing arms and a Panhard rod for lateral location, the whole being coil sprung. In order to make this new chassis configuration work, Claude Hill introduced a small rectangular tube ladder framed chassis, with outstanding torsional and longitudinal stiffness: the result was class leading road holding and ride comfort.

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THE INTERWAR YEARS

ENTER DAVID BROWN

t the end of the war, Gordon Sutherland had acquired sole ownership of Aston Martin Ltd, his father having sold his shares to him for £5. Aston Martin emerged in a good state with excellent facilities, a sound balance sheet and a small but skilled workforce. However, in common with much of industry, resources were extremely difficult to acquire in order to restart car manufacture and the national effort, (requiring as much export as possible), meant the need for a hasty design of a sporting 2 seater tourer suited for the American market. It rapidly became apparent to Gordon Sutherland, that gearing up for this, required a level of resource and financial backing beyond what he could provide; and with a need for a major industrial backer in order to secure supplies of scarce steel and other materials. It was therefore with much regret that he put Aston Martin Ltd up for sale.

2 litre Speed Model, a rakish design that was typical of Aston Martin in the late 1930’s. Augustus Bertelli eventually left Aston Martin and the motor industry, after a serious disagreement with Gordon Sutherland. His deputy, Mr Claude Hill, who would remain with the company until 1956, assumed his role of Chief Designer. Engine and chassis were developed using a variety of prototype cars. First among those was “Donald Duck”, described even at the time as a “curious looking saloon”! Chassis design was further developed with the C Type, which was created to hone the road holding and engine. This introduced small section chassis tubes for the ladder type chassis construction, an all enclosed radiator and integral front wings. Later came another innovative saloon body design, known as “Atom”. It utilised some clever and very advanced unitary body design techniques. While the styling, putting it charitably, might be described as quirky, the resulting car was,

The advertisement announcing the sale of Aston Martin was placed in the Times as 1946 drew to a close and

not withstanding, light, fast and economical and with outstanding handling. The Cotal gearbox was retained.

attracted only one serious indication of interest; Mr David Brown, owner and managing director of David

At this point the 2nd World War intervened and production of all car manufacture ceased. Thereafter until the

Brown Ltd.

war’s end, production was geared to the war effort. “Atom” went on to serve as valuable war transport for Gordon Sutherland.

David Brown, born in 1904, assumed the responsibility for David Brown Ltd in 1932 on the death of his father, Frank, and his uncle Percy. The main business of David Brown Ltd was the design and manufacture of gears and gearboxes, finding their way into the hulls of many warships and merchant vessels and countless other applications. DB Ltd was and remains a nationally important company. However, David Brown also diversified into related mechanical products, including car transmissions, superchargers and similar products. As the 1930’s drew to a close, opportunity was taken to enter into tractor manufacture, commencing production in 1939.

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ENTER DAVID BROWN

David Brown answered the advertisement in his own private capacity. He felt that it was important that the UK had a nationally competitive sports car and being a keen motorist, shared a passion to go racing and win at Le Mans. He saw Aston Martin as the ideal platform from which to achieve that ambition. In deciding whether to make an offer for the Company, he test drove “Atom”, being highly impressed by its roadholding, but felt that it was lacking in power to take advantage of the potential in the car. This convinced him that Aston Martin would need a bigger engine and having seen the impact that the XK 120 1948 launch had, that it had to be a 6 cylinder twin overhead camshaft engine that powered them.

LAGONDA MOTORS

agonda Motors traces its roots back to 1899, when the company was founded by Wilbur Gunn as the Lagonda Engineering Company, beginning in a shed at the bottom of his garden to build small compound steam engines primarily for boat propulsion. In 1900, Wilbur made his first motor cycle, sensing that with the state of transportation, more and more were demanding the convenience and speed available from motorised modes of transport. Initially as with so many start-up businesses, the first products were built from parts bought in from other local light engineering companies, in this case Knights of Staines, from whom he acquired the frames. Wilbur designed and manufactured a small internal combustion engine and adapted the frame to fit. The company prospered and rapidly expanded, producing a succession of well engineered and light weight cars starting with the 12 hp of 1908, then the 14/16 hp using a bought- in 4 cylinder engine made by Coventry Simplex, followed by a 20 hp 4 cylinder model later to be adapted to a more powerful 4 cylinder engine of Lagonda’s own manufacture (the 20 hp,) to a new 6 cylinder model, the 30 hp of Lagonda’s own design and manufacture. Lagonda Motors, as it had been renamed, survived the First World War and by 1919 was back manufacturing high quality sporting cars, concentrating in the carriage trade.

The Claude Hill designed push-rod 2 Litre engine which he had developed, (in David Browns view) was not the way forward. Consequently, he therefore sought to source an alternative engine. This he found with Lagonda Motors.

In the depressions of 1929 and early 1930’s, ownership of Lagonda Motors was passed to Mr Alan Good and the emphasis of the company moved from high performance sporting cars, to the highest quality and luxurious touring cars, starting with the M45, leading progressively through various iterations to the production of a V12 saloon and drop-head of the very highest quality and elegance.

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LAGONDA MOTORS

Throughout this period, it had been the policy to manufacture in house many of the components and as such, Lagonda Motors possessed a large machine shop and associated foundry. At the outset of the 2nd World War, this manufacturing capability was transferred to the support of the war effort and car production ceased for the duration. During the late 1930’s, WO Bentley had joined Lagonda, initially designing and building the LG 45 and then later V12 engined cars. As 1939 approached, he was engaged in developing a replacement model with a new 2.5 litre, 6 cylinder, twin overhead camshaft engine, the initial development of which took place in the last year of war and 1946. The intention then was to restart car production in 1947. However, by war’s end, Alan Good had decided to concentrate the use of these resources into small marine engine production under the trading name Petter Diesels.

DB1 - The first car that was designed with the body for production by Aston Martin. It was fitted with the chassis and 2 litre engine design by Claude Hill. It performed well both as a road car and in competition with the prototype car competing and winning the 1928 Spa 24 hour race for sports cars outright.

M45 Drop head - with Bodywork by Lancefield is very typical of the type of car made by Lagonda from 1934 until the onset of war in 1939 Car manufacture ceased in 1947 and design assets of Lagonda Motors were put up for sale but not the facilities and property. Initially he asked no less than £225,000. This offering attracted a number of potential bidders until the budget of 1947 introduced new taxation rules. The initial expressions of interest evaporated and on learning this, Mr David Brown then made his offer of £50,000 with the intention of mating the Lagonda engine with the chassis design created by Claude Hill and with a 2 seat Touring car of elegant design, subsequently named as the DB1. With the design assets of Lagonda Motors also came a number of design staff, including Chief Styling engineer Frank Feeley, who was to oversee every Aston Martin produced up to the birth of the DB4.

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THE POST WAR YEARS UP TO 1971

nder David Brownâ&#x20AC;&#x2122;s ownership, Aston Martin was for the first time funded to develop and manufacture cars on a significant scale. A dealer network was created, a service centre provided and a full sports racing car programme put in motion. Sales rose, but never seemed quite sufficient to cover the full cost of development and manufacture. The adoption of the WO Bentley engine led to an early break by Claude Hill, in a serious disagreement with David Brown. His departure led to the promotion of Harold Beach who took charge of chassis design under the tutelage of Robert von Eberhorst, late of Auto Union, who was appointed Chief Engineer.

David Brownâ&#x20AC;&#x2122;s reason for purchasing the Lagonda Company. Engine development came under Mr Tadek Marek and initially the DB2 engine was progressively modified to increase power. An increase in size followed to 2.9 litres and after a number of design problems were rectified, it powered the DB2/4 from 1954. The DB2 - powered by the 2.6 litre LB6 engine, established the international reputation of Aston Martin as a manufacturer of cars of the highest performance and comfort. The DB2/4 was designed in the 2 plus 2 format, that was to endure through all subsequent models. An innovative hatchback design, it proved a popular choice for the discerning wealthy, but by 1956, was becoming increasingly outdated and it was clear that an all new model was needed. The DB2/4 was developed progressively until this car was ready, with the DB2/4 Mk II and then with a much revised body, in DB2/4 Mk III form. The LB6 engine was also modified to overcome a number of other design issues and to increase power and torque and emerged as the DBA in 3 litre form with a heavily revised cylinder block and head.

THE POST WAR YEARS UP TO 1971

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THE POST WAR YEARS UP TO 1971

By 1956, Harold Beach was hard at work designing a new platform chassis, Tadek Marek was fast developing a new engine and Touring of Milan was engaged in styling an all new body. The new model became the DB4. The DB4 was first shown to the public in late summer 1958 to instant acclaim. The platform chassis had been intended to use a de-Dion rear suspension, but for reasons of development and production cost, this concept was shelved and it emerged with a well-located conventional rear axle. The body used the Superleggera construction concept of light steel tubes supporting an outer body shell that was both light and strong. By 1958 the engine had grown to 3.7 litre capacity and as foundry capacity was only available in aluminium, emerged as an all alloy engine.

The model when all of the problems encountered with the earlier years of DB4 production were finally eradicated. The resulting car not only had very high performance and road holding for its time, but was superbly refined and proved it was a reliable performer and capable of sustained very high speeds in great comfort. In 1957, the decision was taken to leave Feltham and to move all design and production to the old Tickford Works at Newport Pagnell. The move was to prove highly disruptive with many key workers refusing to move. In consequence there was a significant delay in the production of the DB4, which meant that the first cars were unavailable to the public until late 1959. By 1964, it became clear, as a result of customer demand that better rear seat accommodation was required and an all new replacement was needed. This development was to spawn the design of an all-new V8 engine, designed by Tadek Marek, and heavily revised platform chassis, designed by Harold Beach, which The DB4 set the world alight, reinforcing Aston Martin as a sports car manufacture of the highest

at long last would use Aston Martinâ&#x20AC;&#x2122;s de-Dion rear axle. Body design was entrusted William Towns. To cover

performance, elegance and quality. It was a truly iconic model.

the interim before the car was ready, the DB5 was revised with a longer wheelbase, revised roof profile and improved aerodynamics, becoming the DB6 that was to continue in production until 1970. The DBS was

By the time the DB4 was announced, John Wyer had become General Manager and set about developing it

announced in 1968 to wide acclaim, but as the V8 was unavailable, used the existing 4 litre engine fitted to

for production and to radically improve its early reliability. The DB4 was to progress through 5 distinct design

the DB6 that continued in production alongside.

series before finally emerging in DB5 form as a fully developed and reliable 4 litre car.

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CHANGE OF OWNERSHIP

y 1971, the cost of the all new DBS, unfavourable trading conditions and under pressure from David Brown Ltd shareholders, David Brown sold Aston Martin to Company Developments. The new managing director, William Wilson set about taking cost out of production and realising as much of the asset base as possible, so that a sufficient amount of working capital could be made available to sustain production. The V8 was introduced in the DBS in 1971, just as the fuel crisis was hitting its zenith; unfortunate timing was just one of the reasons why the number sold never matched projections. Production continued in fits and starts as funds could be made available until finally the company was declared insolvent in 1975. In July 1975, two American enthusiasts, Peter Sprague and George Minden (and shortly afterwards Alan Curtis and Dennis Flather), bought the company and took operational control. After further fitful trading, the company was again sold in 1980, this time to Victor Gauntlett, who, as Chairman and Managing Director steered the company until finally securing its long term survival, when the Ford Motor Company bought Aston Martin in 1987.

Picture of Virage - the new model Virage that enabled Aston Martin to stay in business during the early 1990’s and which with Ford’s help secured a production base at Newport Pagnell and helped provide the essential continuity of the Aston Martin tradition into the future. In 1990, Ford announced that the new MD was to be Walter Hayes, who immediately commissioned the design of an all new model. The design brief was to create a beautiful smaller coupe that would attract a significant increase in demand. To make it affordable, it would have to adapt already developed major components in an all-new body. The foundation chosen was the Jaguar XJS platform and AJ6 engine in supercharged form. Ian Callum was entrusted with the new body design and development and production was entrusted to TWR of Bloxham, Oxfordshire, under Chief Engineer Rod Mansfield. A new company Aston Martin Oxford Ltd was formed for the purpose. In 1993, Sir David Brown became life President of Aston Martin Lagonda and gave his permission for the new model to be known as the DB7. The DB7 was announced in 1994. In 1999, the V12 DB7 Vantage was introduced to replace the V8 Coupe. In 2001, the Vanquish was announced. It was to be assembled at Newport Pagnell. In 2003, Aston Martin’s The V8 Vantage and Volante introduced in 1979 - 2 models that the funding and recapitalisation provided by

new production facility at Gaydon was opened and in 2005, DB9 production commenced, under the

the new owners enabled and that secured Aston Martin’s future for a few more years.

leadership of Dr Ulrich Bez, the new Chief Executive.

By 1984, it was clear that a new model was urgently needed to replace the V8 in Vantage and Saloon form and development of the Virage commenced. The platform chassis was revised and electronic controlled fuel injection introduced. The new body design was entrusted to John Heffernan and John Greenley. The Virage was announced in September 1988 with the introduction of the Volante drophead, Vantage and V8 Coupe form. Production finally petered out when superseded with the announcement of a replacement in 2000.

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CHANGE OF OWNERSHIP

In 2006 the new Vantage V8 was announced, a smaller cousin to the DB9. In 2007, it was announced that Ford wished to dispose of Aston Martin. A consortium comprising Kuwaiti investors and David Richards of Pro-Drive, purchased the company. David Richards became Chairman of Aston Martin and Dr Ulrich Bez continued as Chief Executive.

The DB7, the car that finally transformed Aston Martin from a cottage industry into a medium sized international manufacturer of GT cars.

Walter Hayes created the DB7 that secured Aston Martinâ&#x20AC;&#x2122;s future finally for the long term. Dr Ulrich Bez that built so successfully on that foundation and that led to the DB9, Vantage V8 and which finally made Aston Martin a major competitor to the likes of Porsche and Ferrari.

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ASTON MARTIN IN COMPETITION

full racing programme was instituted under John Wyer in 1949. The brief given by David Brown was to be

By 1962 all racing interests had ceased and the company was not to get involved with a full factory racing

delightfully simple, win at Le Mans. The DB2 proved a very competitive car and in 1950, the team consisting

team again until the mid 1990â&#x20AC;&#x2122;s, when in conjunction with Lola, a factory team was reinstituted for the Le

of three DB2 works entries came 5th and 7th overall and first in the 3 litre category.

Mans series. Limited success followed, but they were in competition with the Jaguar Silk Cut Team, and limited development funds and the high fuel consumption of the V8 were major factors inhibiting success.

More success was to follow in 1951 with 2 specially lightened DB2 works entries, the lead car coming in 3rd, the other 5th and a privateer 7th. It was to prove a high point in the Le Mans for a number of years.

Finally in 2005, Dr Ulrich Bez announced an agreement with Pro-Drive to race specially modified DB9 cars

By 1952, the DB3 was ready but never proved fully competitive nor adequately reliable. The DB2 continued

(known as the DBR9) in the Le Mans series races in the USA and Europe. Success followed in the GT1

to be campaigned with conspicuous success, but its competitiveness in the top echelons was becoming

class, against the major competition from the Corvette Team of General Motors. In 2007 Aston Martin finally

impossible to sustain.

won the GT1 class at Le Mans with a 1, 2.

To overcome the disappointing performance of the DB3, a revised design took shape, to reduce weight and drag, this being the DB3S. One of the prettiest sports racing cars of all time, it proved instantly competitive but not always reliable. However, this car proved that Aston Martin were up with the best of the rest of the world, attracting the best drivers and leading to conspicuous success in all of the main racing circuits of Europe and the USA, except at Le Mans. As 1957 approached, it became clear that the LB6 engine was reaching its maximum potential, and an all new engine and chassis was needed to win. This led to the development of the DBR1. Its engine was designed by Tadek Marek, Ted Cutting was entrusted with chassis design and Frank Feeley designed the body. The engine design was initially developed to a 3 litre design brief, but from the outset, Tadek Marek built in the development potential to increase engine size up to 4 litre capacity. The DBR1 was prepared in 3 litre form using the RB6 engine, and proved instantly successful. Among notable successes was the winning of the 1000km Nuerburgring race, in 1957, 1958 and 1959. Failure occurred at Le Mans both in 1957 and 1958 but 1959 proved the high water mark for Aston Martinâ&#x20AC;&#x2122;s racing programme when they finally won Le Mans and the World Sports Car racing championship. The DBR2, a DBR1 with an engine of 4 litre capacity was also campaigned successfully, but not being eligible for the World Sports car racing series, was raced in North America and a number of other unrestricted races in Europe with reasonable success. There was a brief foray into the world of Formula 1 with the DBR4 in 2.5 litre form. In reality, Aston Martin entered Formula 1 at least a year late and the cars were seldom competitive, particularly following the introduction of the rear engined Cooper and Lotus F1 cars. The DBR4 was campaigned in 1958 and 1959, but by then, it was very clear that it was not going to win. The DBR4 proved a major distraction to the Sports Racing car programme, and this was a major contributory factor in the relative failures in 1957 and 1958 at Le Mans. With the winning of the Sports Car Championship in 1959, David Brown announced the official withdrawal of Aston Martin from competition. In reality, Aston Martin continued to keep a small racing team together. A new car, Project 212, was designed and built to race at Le Mans. Some success followed, but the Ferrari GTO, which was the car to beat in 1960, 1961 and 1962, relatively outclassed it. Two other Project cars followed, most notably Project 215, which was the fastest car recorded down the Mulsanne straight. The company also went racing with the DB4 GT with success, though it rarely won races consistently.

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CHAPTER TWO

The DB2/4 MkIII - A Car for All Time

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DB2 DEVELOPMENT HISTORY

ased on what became known as the DB1, the DB2 design brief was for a car capable of winning the World Sports Car championship at Le Mans. David Brown took a strategic decision that a new engine would be required, preferably 6 cylinder of at least 2.5 litre capacity. Additionally, it would need to be good looking, streamlined and modern in concept, with excellent road holding and race worthy. Lightness would be a key issue and to that end, the body had to be in light alloy. Furthermore, the chassis would need to be rigid, yet light. Following Jaguar’s exciting new “XK” twin overhead camshaft engine that was launched with the announcement of the XK120 in 1947, David Brown quickly concluded that nothing less was suitable for his new car. Designed first and foremost as a high performance sports car, the design brief specified only two seats, with only passing regard being given for luggage. In practice, most drivers stowed their luggage behind the driver and passenger. The design specification required therefore, an engine with high specific output, with a twin overhead camshaft configuration of 2.6 litre capacity and with growth potential beyond. To obtain the speed and hence power that would give race winning speeds, power out put would need to be well in excess of 100 bhp in race tune. Chassis design was to be based on a lightweight but very rigid form of space frame, and was to utilise the front and rear suspension design demonstrated so abley by the ATOM and also by the highly successful Aston Martin special that won the SPA 24 hour sports car race outright in 1948. To that end, the trailing arm front suspension was to be continued and with a well located rear axle utilising twin trailing arms and Panhard rod for lateral location. This design brief was one that the then Chief Designer Claude Hill felt he could meet with his own car design, and that in particular, his 4 cylinder engine could be readily developed to provide the high power need to achieve race winning potential. It was quite clear that there was to be no meeting of minds with Aston Martin’s new owner, and Claude Hill left the company and a new chief designer, Harold Beach was appointed to lead the new car design.

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DB2 DEVELOPMENT HISTORY

The design of the DB2 body was entrusted to Frank Feeley, late of Lagonda. Developed from the DB1 car, it featured a fully integrated frontal design, revised radiator grille, with the bonnet and front wings opening in unit and pivoted at the front, thus affording excellent accessibility to engine, front suspension and steering. The car body and rear was in unit and streamlined. The body and bonnet assemblies were fabricated in aluminium alloy, with a steel tube bracing structure to provide support and rigidity to the bonnet assembly. The sills, A and B posts were constructed in steel to impart a strong foundation for the aluminium body shell, and this steel structure was then bolted and welded to the chassis.. Handsome and workmanlike, it gave the DB2 a lithe, light and handsome appearance that was functional, elegant and modern in concept. It was also a very well balanced design. In 1950, the DB2 Drop Head Coupe was launched, of which some 98 examples were built, until superseded by the DB2/4. A 2 seater, it is a very elegant design, particularly with the hood down.-

CHASSIS DEVELOPMENT The key objective for the DB2 chassis was to provide a significant additional amount of longitudinal and torsional rigidity, in the interests of ensuring class leading road holding and handling. To achieve that, the main chassis longitudinal structure was doubled to impart a greater depth in the main sill sections and cross braced. To provide additional torsional rigidity, the scuttle structure integrated the A posts, double skinned and cross-braced.

The upper sections were led forward from the scuttle fabrication and heavily cross-braced, this giving excellent torsional bending properties. The sill bracing was welded to the scuttle assembly thus providing excellent stress transference for the front suspension loads. The main rear suspension loads were taken from the rear suspension coil spring mountings, which were in turn supported by a strong, cantilevered structure that led from the deep sill beam assembly. The chassis sections were constructed form high strength steel, utilising small cross section rectangular steel tubes. The resulting structure was both rigid and lightweight, thereby fully satisfying the design brief.

SUSPENSION Much of the suspension and steering assembly design was developed and trialled in the prototype car ATOM, which was used as a test bed, and which, David Brown having driven, convinced him that this was a car design with real promise and ability. The design was carried forward and developed for the DB1, and in turn the DB2. Meanwhile, a racing chassis had been developed and as a private entry, entered into the 1947 Spa 24 hour race for Sports and racing cars. Known as the SPA special, it was privately prepared and entered and against significant competition from pre-war Delahayes, Maseratii and others came way with the honours. The design concepts that led to the choosing of a trailing arm front suspension design stemmed from a concern to reduce unsprung weight, to provide a good degree of roll resistance and minimal change in camber angle regardless of front suspension deflection. One of the advantages of a railing arm suspension was that it provided a high roll centre thus naturally reducing roll.. In addition, the integration of a torsion tube with the lower trailing arm mounting gave added roll resistance.

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CHASSIS DEVELOPMENT The upper trailing arms were created from the lever arm dampers. The lower trailing arms were splined into the front anti-roll bar, the torque tube being contained within a cylindrical aluminium casing and pivoted at either end with roller bearings. The kingpin assemblies were conventional and adjustable for king pin inclination. Steering was effected with a cam and roller Marles steering box, leading to a set of complicated divided steering track arms, the whole designed to minimise the effects of roll and bump steer. The conventional rear axle was suspended with coil springs and located fore and aft with twin trailing arms, following design principles developed with the ATOM. Transverse loads were controlled using a Panhard rod. Taken as a whole this provided excellent fore and aft, torque and lateral location and control. Damping was provided with conventional lever arm shock absorbers. The design realised significant handling and road-holding benefits over the then standard leaf sprung suspension in common use. It also endowed the car with a general agility and cornering ability to ensure that as a GT racing car, it would be highly competitive in Sports and GT events of the time.

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ENGINE AND TRANSMISSION DEVELOPMENTS

The engine design owes its origins to ideas developed by WO Bentley, while he was Chief Engineer at Lagonda Motors during the mid to late 1930s, and after he had departed from Bentley, following the takeover of Bentley Motors by Rolls Royce. His brief was to conceive of an engine design for a post war world. Realising that materials and fuel would be in short supply and costly, it was felt that a modestly sized engine was required and this led to a design based on an engine capacity of 2.6 litres, which would run on the low 80 Octane “pool” petrol than available. It was also agreed that it should be a 6 cylinder design. Refinement was central, as also a high power to weight ratio. As a consequence, the design brief stipulated twin overhead camshafts, with generously sized inlet and exhaust valves inclined at a 60 deg included angle into a hemispherical combustion chamber. It was well known at the time that to achieve a high degree of refinement, while minimising weight, required a rigid crankcase and generously sized bearings, particularly as it was felt in the interests of economy and complexity, that a four bearing crankshaft design would be utilised. To allow excellent cooling and minimise weight, a wet liner design was adopted, using bottom-seated liners, which could then be clammed down by the cylinder head. The crankcase design principle was that if each main bearing could be contained within two split hemispherical aluminium segments, which could then be inserted into the crankcase housing with a light interference fit when cold, it would create a highly rigid assembly hot, as the iron casting of the crankcase/cylinder block would expand noticeably less than the aluminium bearing housings. The heavy clamping loads thereby created, it was hoped would lead to a very rigid assembly. The idea was excellent in theory, but over time, fretting occurred in service and the clamping loads decreased, leading to problems. The launch of the DB2/4 led to an inevitable increase in weight and to counteract the capacity of the engine was increased from 2.6 to 2.9 litres. In this guise, the standard engine developed up to 140 bhp in 3 litre form., and endowed the DB2/4 with a maximum speed of close to 120 mph and a 0 to 60 time of 10.5 secs, these being close to the recorded performance figures for the DB2. The increase in engine capacity was achieved by the offsetting of alternate cylinder bores about the centre line of the engine and using modified connecting rods to compensate.

The Vantage engine An uprated 2.6 litre engine was offered as an optional extra on the DB2. It was fitted with modified inlet manifolds and ports, increased 8.0 to 1 compression and bigger 1 ¾ in SU carburettors. Known as the Vantage engine, it increased peak engine power from 105bhp to 125 bhp, a useful increase and gave noticeably improved acceleration. The Vantage engine was carried over to the DB 2/4 in both 2.6 and 3 litre variants.

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GEARBOX David Brown was insistent, as a major gear manufacturer that it was to be his firm’s own gearbox that would be used in the DB2. As was common with nearly all car manufacturers of the late 1940’s, the design brief stipulated 4 speeds, with synchromesh on 2nd, 3rd and top. In service experience was mixed. Used in racing, the gearbox quickly gained a reputation for unreliability and difficult gear changing.. In service the gearbox proved satisfactory, but was never considered to be as good as the other aspects of the car. A complicated column gear change mechanism was designed of doubtful quality in the DB2 and DB2/4 that followed, in conformance with a practice adopted across the industry, in the drive to export as many cars as possible to America. These were soon discarded and the more usual central gearlever position was re-adopted.

THE DB2/4

. he DB2/4 became one of the very first cars to offer such a facility and it proved an immediate hit with the customer. The result was and is a very practical and convenient solution. The DB2 came with a divided front windscreen. With the DB2/4 about to be launched, the divided windscreen was discarded in favour of a full width curved windscreen, taking advantage of developments in the manufacture of toughened Triplex glass. Anticipating that demand would increase above those for the DB2, also prompted Aston Martin to contract with Mulliners in Birmingham for the manufacture and assembly of the bodies, and in turn, they re-engineered aspects of the body design. Among features that they introduced were cast alloy sills, changes to the A and B posts and updating of the interior seating.

BRAKING SYSTEM

Engine developments Moves to increase the size of the engine initially grew out of the racing programme. It was felt that an increase in the cylinder bore would be the most practical way to go, but as money for a new engine block casting

The brake design was chosen, very much with racing in mind. Generously sized drum brakes were adopted, with excellent cooling which gave for the time an excellent resistance to fade, following hard use. Alfin brakes were chosen, utilising aluminium drums with cast iron inserts for brake liners. Front brakes were both leading and trailing. The rear brakes utilised a fully floating design concept, the whole resulting, for the time with a car with exceptional braking ability.

could not be afforded, the increase in the bore could only be achieved by offsetting the liners to fit. The resulting increase was small but useful, with engine capacity rising from 2.6 to 2.9 litres.. The bore offsets was initially accommodated on the connecting rod gudgeon bearings. The end result was a calamitous failure, prompting a redesign. Instead the 2.5 mm offset was accommodated at the crankpin end, which proved durable. Usable power then rose from 120 bhp to near 140 bhp, thus satisfactorily offsetting the weight increase following the body redesign.

OTHER DB2 DEVELOPMENTS

The special Body DB2s and DB2/4s There have been a number of DB2 and DB2/4s which,, at the request of the Carrossorie concerned, have had chassis delivered, upon which they have constructed their own bodies to special order. These include in

Another innovation for the time was the fitment of 2 speed self parking windscreen wipers. The DB2 was further developed as a 2 seat drophead coupe of particularly elegant design. The design concept and general design of the hood was to be one that Aston Martin broadly continued with right up to the launch of the DB7 Volante. The hood was unlined.

Europe; Graber of Switzerland and Vignale (2 of which were originally built but only 1 example is now thought to exist). In addition there was Arnolt of the USA who created a particularly nice 2 seater roadster body. These roadster bodies were designed and constructed by Bertone to a design commissioned by Arnolt. In all, there were some 17 special bodied cars, of which a total of 5 were constructed using the DB2 rolling chassis, with the remainder on DB2/4 rolling chassis.

THE DB2/4

THE DB MKIII In 1953, the chief designer, Eberan von Eberhorst, left Aston Martin to rejoin Auto Union and a young but

Within a year of the launch of the DB2, owners were already saying that they would like 2 additional seats so that they could take their family as well. It was also apparent that this would significantly widen the appeal of the car, and with it, bring an increase in sales. Recognising that this would also add weight, Aston Martin were prompted to start a model development in 2 key areas, these being to add 2 additional rear seats and an enlarging of the engine capacity to support an increase in engine torque and power. The first element required that the roof height was increased and extended allowing the inclusion of 2 occasional seats, that would be suitable for children or which an adult could sit on for short distances. While the increase in roof height was relatively easy to design, the rear of the body design posed real problems until, in a brainwave, Frank Feeley, the body stylist and designer, had the idea of an enlarged opening rear window, creating one of the world’s first hatchbacks. The hatchback style opening rear window allowed easy access to the space behind the rear seats, bringing with it convenience and space for the family luggage.

highly competent engineer, Tadek Marek, took his place. By 1954, John Wyer was appointed General Manager, and with it, he started a world wide tour of Aston Martin dealers. The message that clearly came back was that the DB2/4 in its present shape was selling reasonably well, but that its replacement would be needed as soon as possible, if sales volumes were to be maintained.. As there was no prospect of its replacement being ready before 1958, a revamp would be needed as an interim measure. This led to the design brief for the DB 2/4 MkII and MkIII. The DB2/4 MkII should be seen as interim step to introducing the Mk III, and with its introduction, body manufacture was moved from Mulliners to Tickfords in Newport Pagnell.. Tickford had been in the coach building business since the dawn of motoring and had a long and proud association with the British coachbuilding industry. Their current customer, Alvis was phasing out the 3 litre and as Alvis was entering discussions with Willowbrook to construct a new body designed by Graber of Switzerland, an opportunity to use the facilities and skill in Newport Pagnell for future Aston Martin manufacture beckoned.

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THE DB MKIII ENGINE REDESIGN Of Polish origin, Tadek Marek’s first task was to re-engineer the design of the engine, to deal with a number of significant problems. These included significant modifications to the engine block, improving cylinder head port design to enable bigger valves to be used and use of a 14mm plug in place of the previous 10mm. Also included was an uprating of the engine oil pump, as a means of increasing oil pressure and an increase in sump capacity. In addition the crankshaft was modified to increase its stiffness and improve case hardening, all of which was aimed at enhancing smoothness and reliability. These and other modifications stemmed from hard won racing experience. An overdrive was offered for the first time, reflecting and anticipating more modern fast road design.

THE UPDATED DB MKIII BODY The major changes included a new bonnet and grill, interior trim improvements and a much improved and elegant dashboard and instrument panel. At the rear, the shape was tidied and better integrated, with “cathedral” type rear lights, The new grille, reflecting the design of the DB3S, was the work of Frank Feeley and was a marked improvement and so came about the key design cue that has remained with Aston Martin to this day, giving the marque instant recognition across the world. The same styling cue was mirrored in the instrument panel design, another feature that was to endure through to the introduction of the DBS and V8 era. The end result was a most delightful and elegant car. Sales recovered.

DB MKIII CHASSIS AND SUSPENSION CHANGES The chassis itself would remain essentially unchanged, but a big improvement was made with the brakes, with the introduction of front wheel disc brakes. At a stroke, one of the few concerns, namely a tendency for brake fade following hard and continuous use was eliminated and a tendency after some in service use, for uneven braking banished.

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CHAPTER THREE

History and Restoration of a DB 2/4 MK III

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HISTORY OF DB2/4 MK III - REG NO: WYE 847 AM/300/3/1815

ENGINE NO: DBA/1404

his an unusual car in that it has almost a continuous history since the date it was first registered in 1959. The purchaser of the Aston Martin was the Africore Mining Company of Berkley Square , London. We can be fairly sure that its first user would have been most probably the then Managing Director or Chairman. Its date of first registration and delivery was the 24 April, 1959 and was supplied direct from Aston Martin. The build sheet for the car shows that it was a standard non-overdrive car, and painted originally in Sea Green with White gold leather upholstery. We can be fairly sure that this would have been to special order. Unusually, there were no recorded options purchased with the car. Service work carried out during its first 17,000 miles cover both routine servicing, but interestingly makes reference to the Gearbox 1st gear and layshaft being changed after no more than 10,000 miles. It appears that after 17473 miles, the car was repaired following an accident and the car was re-cellulosed in Snow Shadow Grey. At the same time a steering box oil seal was replaced. And by 17982, miles the car was fitted with its second set of new tyres. Perusal of the duplicate green registration document suggests that the car was retained by the Africore Mining Company until 5 January , 1962, when it was sold to a Mr Hugh. R. Hutton of Kings Road, Chelsea, London. The next recorded event is March, 1966, when the car was registered in the name of Mr MJ Garbutt of Guildford, being a motor trader. In 1967 the car was again sold, this time to Mr KJ Conyers also of Guildford. A few months later the car was again sold to Mr JW Herring, AMOC Membership No. 2789, of Leatherhead, Surrey, the time being January, 1968. John Herring used the car from purchase in January 1968 to August 1968, then as he had another DB2 he decided to set about the renovation of WYE 847. Work was started and considerable work was completed as detailed in John Herring Notes, however due to family, work and home changes, the renovation was never completed and the car essentially remained unused until the car was sold to Mr Ronald D. Powell, AMOC No. 23792, the present owner, in July 2009, 41 years later.

EARLY RESTORATION As stated above, following the initial use of the car, John Herring embarked upon a full restoration and the following brief summary are based upon his notes, which are long, comprehensive and detailed. Copies of these notes are in the Annex along with detailed notes of what was purchased and a running list of expenditure. The scope included chassis, suspension, wheels, steering, engine, body, electrical, brakes, transmission and trim. Detailing of the engine bay and chassis was a primary objective, as was a strong desire to overhaul the mechanics, including engine, suspension, brakes and electrical systems.

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EARLY RESTORATION

There is a general reference to bodywork refurbishment, the bodywork being given to Robert Laidlaws of Wembley, which was completed December 1970 for the sum of £120. Work included replacing or repairing door skins, side panels, bonnet and sills. In addition, it provides details of re-upholstering, and general refurbishment of the interior, including leatherwork, carpets and headlining. The engine was given a comprehensive overhaul and at the same time steps were taken to measure bore wear and to assess the general condition of pistons, liners and and crankshaft. With the engine reassembled and block repainted, there is a reference to the fitment of a new gearbox complete with an overdrive supplied by SE Robinsons of Bedford. It is worth noting that adaptation of the original gearbox is difficult, as to fit an

MAJOR BODYWORK

y 1995, Mr Herring was resident in Truro and not unsurprisingly, the body was showing its age and much in need of comprehensive restoration. The bodywork was entrusted JR Pryor’s in Truro. The notes indicate replacement of the sills on both sides, stripping of all paintwork, cutting out and removal of any corroded aluminium from the sponsons panels each side, a common area, as also front and rear wheel arches. Replacement of the bonnet hinges was another common area for corrosion damage and these were replaced. After detailed panel preparation to remove numerous dents, the body was primed, and repainted in British Racing Green. At the same time, the underside was undersealed with black Shultz. The cost of all this work was £1000. Bumpers front and back were also rechromed. Opportunity was also taken to carry out a further top overhaul on

overdrive requires replacement of the gearbox main-shaft, a new adaptor plate between gearbox and overdrive

the engine.

unit, eccentric cam to power the overdrive oil pump and different gearbox change linkage. Other detailed

Mr Herring kept copious notes of what he did and these are in the in the Appendix.

notes refer to a variety of items, including stainless steel exhaust, enamelled exhaust manifolds and numerous

By 2001, Mr Herring was again resident in West Sussex and the records show a number of routine

gaskets etc. There are further detailed notes of the itemised costs made in 1968, which make for interesting

replacement parts which were invariably obtained from Aston Service Dorset and in more recent years from Tim

comparison in later years.

Stamper. The Build sheets were obtained from Aston Service Dorset who also authenticated the car’s origin and

The suspension overhaul included new king pin bearings, as well as detailing the front and rear suspension

date of manufacture.

with polished front spring towers and cadmium plated front and rear suspension springs. Other items attended to included the brakes, with overhauled front callipers, new rear brake shoes, master cylinder and

NEW OWNER

new brake hoses. There is correspondence between Mr Herring and several companies who were requested to supply replacement chromed spokes for the wheels. In 1974, further serious engine work was undertaken, this time with the dismantling of the entire engine and

In 2009 Mr Herring regretfully determined that the car should be sold, as he himself had moved into a retirement

on this occasion fitting new pistons, rings, main and big end bearings. At that time an attempt was made to fit

home. The car was then advertised and duly purchased by Ron Powell in June 2009. On purchase, the body

an anti theft system, but the installation proved unsuccessful.

itself remained essentially original and in sound condition. The interior had been refurbished and restored with new beige leather and carpets, while at the same time, the car had been stripped and repainted in British Racing Green.

Visit to Works Service – July 2009 At collection, July 9th 2009, the car was taken to Works Service in Newport Pagnell for recommissioning, detailed check up, brake and suspension overhaul and attending to a major engine water leak, which necessitated removal of the cylinder head. The radiator was also reconditioned and an MoT obtained. When examined by Works Service, the single greatest concern was the major water leak, where it was feared that the cylinder block had been severely damaged. Other problems, consistent with a long period of storage, included binding brakes, leaking brake cylinders, water pump leak, weeping shock absorbers and the inevitable electrical gremlins, these items were all attended to. The major water leak turning out to be caused by 2 failed core plugs, nether of which was evident without removal of the cylinder head. The car was presented to Ron Powell, Wednesday evening October 21 2009, and a test drive provided by Gordon Higgs Newport Pagnell’s Works Service Heritage Driver. A good 100 mph was achieved in a very short time ..... stunning! The car was then handed over to Ron for his first Drive. After this first Drive, a diary of Daily Use Notes has been kept and these can be referred to in a section later in this book.

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Visit to Aston Workshop - April 2010 In April of 2010 and after only 1138 miles, it became evident that the cylinder head gasket had failed, engine oil leaks were substantial and there were other snags, all of which required attention. It was decided that the best course of action was to entrust the car to the Aston Workshop. On removal of the cylinder head, it became immediately clear that the cylinder head would require re-facing. Another problem revealed itself, namely water leaking past a number of valve guides. A loose plug in the main oil gallery within the cylinder head, created another major oil leak. Given that rectifying these problems would necessitate a substantial rebuild of the cylinder head, it was readily agreed that an unleaded conversion should be undertaken. Items of paintwork, detailed fettling and general tidying were undertaken. This included the welding up of mounting holes in the offside wing from a previously fitted wing mirror, typical of the numerous snags that were dealt with at that time.

Notes on the unleaded conversion When the DB Mk III engine was developed, the cast iron cylinder head was modified with enlarged, better breathing inlet and exhaust ports, a 16mm plug, but in so doing, Tadek Marek as Chief Engineer, deleted fitment of valve seats, to minimise the scrapage rate while machining the cylinder heads during manufacture. Being cast iron, the quality of the valve seating was perfectly acceptable during the era of leaded fuel. However, with the banning of leaded fuel, except through a few authorised sites, the dangers of valve seat recession became significant. To counter this problem, it is possible to use lead substitute additives and these can be generally acceptable for normal road use provided high and prolonged engine speeds are avoided. To provide a long term solution, it becomes necessary to fit hardened stellite valve seats and valves and to replace the valve guides with ones made with phosphor bronze. The risk with the DBA engine is that the casting thickness in the vicinity of the exhaust and inlet ports can be thin and consequently, when fitting valve seats, the thickness of the head casting is such that there is a real danger of cracks developing between valve seat and spark plug, leading to valve seatings detaching and leakage of water into the cylinder. In addition, over time, water can also leak past valve guides for the same reason. A replacement cylinder head is now available, manufactured in aluminium that has been designed to eliminate all of the DBA head design weaknesses. However, it can be possible to modify the existing cylinder head, provided care is exercised. In this case the latter course was chosen and the conversion was completely successful. Parts fitted or replaced included the valve seats, valves and guides and of course a complete cylinder head gasket set. Since being collected from the Aston Workshop in late May, WYE 847 has performed faultlessly. As an overdrive fitted car, it has the ability to cruise comfortably at motorway cruising speeds quietly, comfortably and with surprising economy and this capability its new owner, Ron Powell has taken full advantage of. On its first long distance trip, Ron noted that he averaged close to 70mph and achieved close to 30 miles per gallon. The authors experience with a near identical car demonstrates this is no fluke. Needless to say its new owner is delighted and much looking forward to many more miles when he has the time.

Illustrated on following page WYE 847 on test at Beamish driven by Keith Slater.

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