As a small start-up company competing against long established automotive concerns such as Ferrari, Colin Chapman’s Lotus Engineering Company did not have the capability to gain advantage through advanced engine design, or even via the design of most of the other major mechanical systems. Most such components were commercially sourced, and so the only way a decisive advantage could be obtained was through an uncompromising emphasis on gaining performance “edges” from the remaining design elements of structure, body, and suspension. Because the automotive performance aspects of acceleration, braking, and handling are so dependent on various vehicle mass properties the optimization of those mass properties became the “Holy Grail” of Lotus design as directed by Colin Chapman.

1. Brian Paul Wiegand, PE
74TH SAWE International Conference on Mass Properties Engineering
Alexandria, VA, 18-22 May 2015

2. 1928 – BORN ANTHONY COLIN BRUCE CHAPMAN.
1944 – MET FUTURE WIFE HAZEL WILLIAMS.
1945 – ENTERED UNIVERSITY COLLEGE OF LONDON (PART OF U of L).
1946 – STARTED USED CAR BUSINESS WITH CLASSMATE COLIN DARE.
1947 – BEGAN MAKING COMPETITION CARS (LOTUS MK I) &
RACE DRIVING (ENGLISH “TRIALS”).
1948 – LEARNED TO FLY, SERVED IN THE RAF, WON 2 CLASS VICTORIES.
1949 – B. SC. DEGREE IN STRUCTURAL ENGINEERING, BUILT LOTUS MK II.
1950 – EMPLOYED BY BRITISH ALUMINUM COMPANY, WON CLASS AT
SILVERSTONE (INTERNATIONAL RACE TRACK).
1951 – BUILT LOTUS MK III, PARTNERED WITH THE ALLEN BROTHERS.
1952 – BUILT LOTUS MK IV, FOUNDED LOTUS ENGINEERING CO. WITH THE
ALLENS, DESIGNED MK V, BUILT FIRST “PRODUCTION” CAR: LOTUS MK
VI (QUANTITY 110).
1953 – STARTED MK VII (CLAIRMONTE SPECIAL), BOUGHT OUT THE ALLENS,
HIRED AERONAUTICAL ENGINEERS, STARTED LOTUS MK VIII.
1954 – WED HAZIL WILLIAMS, FINISHED MK VIII, DROVE FASTEST LAP AT
OULTON PARK, WON CLASS AT SILVERSTONE.
1955 – QUIT JOB TO BE LOTUS DIRECTOR FULL TIME, BUILT MK IX & MK X.
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3. THE LOTUS ENGINEERING COMPANY WAS
FOUNDED BY CHAPMAN ON 1 JANUARY
1952 WITH VIRUALLY NO CAPITAL.
ENGINES, GUAGES, TRANSMISSIONS,
DIFFERENTIALS, AND MOST OTHER
COMPONENTS WERE PURCHASED. THE
MAIN WAY THAT LOTUS VEHICLES COULD
BE DIFFERENTIATED FROM OTHER
VEHICLES AND GAIN A COMPETITIVE EDGE
WAS THROUGH MASS PROPERTIES, AND IN
PARTICULAR THE RUTHLESS PURSUIT OF
MINIMUM WEIGHT.
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4. 1. SUSPENSION
 IFS & IRS
 SOFT SPRINGING
 HARD DAMPING
 ANTI-ROLL BARS
 MINIMUM CAMBER CHANGE
 MINIMUM UNSPRUNG WEIGHT & MINIMUM
ROTATIONAL INERTIA (MINIMUM GYROSCOPIC
REACTION)
2. AERODYNAMICS
 MINIMUM DRAG (REDUCE Cd & FRONTAL AREA)
 NEGATIVE LIFT (WINGS, BODY, GROUND EFFECT )
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5. SINCE ENGINE WAS USUALLY PURCHASED IT
WAS A “GIVEN WEIGHT”:
FOR EXAMPLE, THE LOTUS MK IX WEIGHT:
Lotus Mk IX Weight = 5 × Coventry Climax 1098cc
1080 lb = 5 × 215 lb
1080 lb ≈ 1075 lb
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First Estimate of Weight = 5 × Engine Weight

6. CHAPMAN WITH REGARD TO THE 1957
MK XII F2 RACE CAR:
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“Fuel comes from a 12 gallon fuel tank mounted
amidships over the driver’s legs in the usual Lotus
practice of minimizing the handling changes
which can take place as the fuel level drops. With
only this tank in the car the weight distribution is
53% on the rear wheels and 47% on the front. An
[additional, for endurance races] 10 gallon tank
can be mounted in the tail, which if used gives a
60/40 [rear/front] weight distribution.”

7. CHAPMAN WITH REGARD TO THE 1957
MK XII F2 RACE CAR:
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“I realized that the high-speed F2 car would
produce a further increase in gyroscopic
loading if the swing axle were retained, and as
I feel that the limit must nearly have been
reached I decided to adopt a fairly
conventional wishbone layout. We now have
double wishbone location with the front
member of the top wishbone doubling as an
anti-roll bar; the springing and damping still
being effected by one direct acting unit.”

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LATER REAR ENGINE DESIGNS
OBVIATED SUCH CONTORTIONS,
BUT ALLOWED CHAPMAN TO
RECLINE THE DRIVER’S POSITION
AS MUCH AS 55 DEGREE FROM
THE VERTICAL…
…REDUCING VCG & FRONTAL
AREA.

9. “I remember having great difficulty adjusting
myself to that [seat] position. The front
wheels seemed much higher than eye level…”
“It was a great benefit for the designers from an
aerodynamic point of view, but…it held some
difficulties for the driver.”
Jim Clark
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The 1960 Eighteen, the first mid-engine Lotus, represented
a reluctant break with earlier Chapman design philosophy:
“The rear-engine (sic) layout offers several
advantages for Formula 1…low frontal
area, low center of gravity, no propeller
shaft problems, and minimum power
loss…The chief disadvantage…is a low
polar moment of inertia.”

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By 1970, when the radical wedge-shaped Lotus 72 was
introduced, the desirability of a low polar moment of
inertia had been long incorporated into Chapman’s design
philosophy:
TBD

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13. “Weight saving is a process which…is open to criticism if it results in
unreliability, or breakages under normal use, but there is no doubt that a
well-designed and properly constructed light-weight car can stand up to
very hard use.”
“Instead of reducing weight, however, it is better to design light in the
first place, modifying any components which may show signs of stress
during development…”
“The total weight of a racing car…is…determined by the weight of the
engine; if this can be decreased by one pound then the rest of the car can be
made four pounds lighter.”
“…tyres and wheels are…critical factor and their weight has a
considerable influence on the car as a whole…The job of the designer is to
keep the right relationship between sprung and unsprung weight…”
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1. SIMPLEST AND MOST DIRECT
DESIGN.
2. MINIMUM BODY &
STRUCTURE.
3. INDIVIDUAL COMPONENTS
SERVE MULTIPLE FUNCTIONS.
4. MINIMUM FUEL & OIL.

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“A racing car has only ONE objective: to WIN
races…it does not matter how clever it is, or how
inexpensive, or how easy to maintain, or even how
safe; if it does not…win it is NOTHING!”
“…increasing the surplus of power…over total
resistance…is BY FAR the most paramount item of
performance…every other consideration MUST be
secondary to achieving absolute minimum dead
weight.”

16. “Designing as light as possible, then waiting for
things to fail in use (there was virtually no
budget for pre-production testing) so that those
specific pieces would then be appropriately
strengthened, was the traditional Lotus
(Chapman) way of obtaining an optimum
structure.”
Karl Ludvigsen
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“I was becoming unhappy about the reliability of
the car. Vital bits kept falling off, like the steering
wheel! He cut a lot of corners, did Colin, and made
things lighter than they probably should have been.”
Cliff Allison
“In one car at Monza… the mechanics found
fourteen major breaks in the chassis. I had breaks in
the steering, wheels fell off, wishbones breaking,
anything that could happen to a car.”
Innes Ireland

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“When we first got together, Colin said ‘Mario, I always
want to make a car as light as possible’. I said ‘Well, Colin,
I want to live as long as possible. I guess we need to talk’.”
Mario Andretti
“Did I think the Lotus way of doing things was good? No.
We had several structural failures in those cars. But at the
time I felt it was the price you paid for getting something
significantly better.” Dan Gurney
“I always reckoned that Colin had the ability to design a
winning car. But what worried me was that it might kill me
before that happened! I had all sorts of problems with
Lotuses. They were all very, very light…” Cliff Allison

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Stirling Moss (twice badly injured, 1960 and 1962),
Alan Stacey (d. 1960), Ricardo Rodríguez (d.
1962), Gary Hocking (d. 1962) Mike Taylor
(severely injured in 1960 when Lotus 18 steering
column broke in two, he sued Lotus for damages
and won), Jim Clark (d. 1968), Mike Spence (d.
1968), Bobby Marshman (d. 1964), Graham Hill
(injured in 1969, but died piloting his private
plane in 1975), Jochen Rindt (d. 1970), and Ronnie
Peterson (d. 1978).

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DUE TO:
1. RUTHLESSNESS
2. CHARM AND MANIPULATION
3. SELF-PROMOTION
4. FINANCIAL CHICANERY
5. TECHNICAL INNOVATION

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American automotive exec John Z. DeLorean
established the DeLorean Motor Company with
British government backing as a means to revive
the impoverished Belfast area of Northern Ireland.
The design errors and mismanagement regarding
the production of the subsequent DMC-12 would
become the stuff of case histories for business
students. The prototype vehicle appeared in 1976,
production began in 1981, and the company was
out of business by 1983.

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In 1978 Chapman agreed to partner with
DeLorean and have Lotus redesign the DMC-12
vehicle. By 1981 the redesign work was finished,
but an embezzlement scandal was to begin.
Some $17 million (£11.5 million) in UK
government funding had disappeared. Fred
Bushell, Lotus CFO, would serve four years
imprisonment for his role. John DeLorean would
ultimately lose his personal fortune to multiple
civil suits.

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PARTIAL LIST OF “INNOVATIONS”:
COIL-OVER-DAMPER UNIT
WOBBLY-WEB WHEELS
CHAPMAN STRUT
BELLCRANK SUSPENSION
ALL COMPOSITE CHASSIS
BACKBONE CHASSIS
VARI (VACCUUM ASSISTED RESIN INFUSION)
NON-AUTOMOTIVE SPONSORSHIP IN F1
GROUND EFFECTS

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1956 CHAPMAN CRASHES IN PRACTICE @ FRENCH GP; QUITS RACE DRIVING.
1957 LOTUS XI WINS INDEX OF PERFORMANCE @ LE MANS, MARKETS FIRST ROAD CARS
LOTUS SEVEN & LOTUS ELITE.
1958 FIRST F1 RACE @ MONACO GP, LOTUS XII PLACES FOURTH @ BELGIAN GP.
1960 FIRST “REAR” ENGINE DESIGN LOTUS 18, 1st LOTUS (PRIVATE ENTRY) F1 WIN @ MONACO
GP.
1961 INNES IRELAND SCORES FIRST TEAM LOTUS F1 WIN @ WATKINS GLEN.
1963 JIM CLARK IN LOTUS 29 PLACES SECOND @ INDY 500. CLARK WORLD DRIVER’S
CHAMPION, LOTUS WORLD CONSTRUCTOR’S CHAMPION .
1965 JIM CLARK WINS INDY 500. CLARK WORLD DRIVER’S CHAMPION, LOTUS WORLD
CONSTRUCTOR’S CHAMPION .
1968 LOTUS IPO MAKES CHAPMAN MULTI-MILLIONAIR. WEDGE SHAPE, TURBINE POWERED
LOTUS 56 DEBUTS @ INDY. JIM CLARK KILLED.
1970 CHAPMAN NAMED “COMMANDER OF THE BRITISH EMPIRE” (CBE). LOW YAW INERTIA
LOTUS TYPE 72 DEBUTS. JOCHIM RINDT KILLED BUT POSTHUMOUSLY WINS WORLD
DRIVER’S CHAMPIONSHIP. LOTUS WINS WORLD CONSTRUCTOR’S CHAMPIONSHIP.
1971 CHAPMAN ACQUIRES MOONRAKER BOATS &TECHNOCRAFT COMPANIES.
1972 EMERSON FITTIPALDI WORLD DRIVER’S CHAMP, LOTUS WORLD CONSTRUCTOR’S CHAMP.
1973 FITTIPALDI & PETERSON 2nd & 3rd FOR WORLD DRIVER’S CHAMP, LOTUS WORLD
CONSTRUCTOR’S CHAMP.
1976 CHAPMAN’S FATHER KILLED IN ROAD ACCIDENT.
1978 LOTUS SIGNS ON TO REDESIGN DeLOREAN DMC-12. MARIO ANDRETTI WINS WORLD
DRIVER’S CHAMPIONSHIP , LOTUS WORLD CONSTRUCTOR’S CHAMP.
1980 CHAPMAN BEGINS MICROLIGHT AIRCRAFT COMPANY WITH BURT RUTAN.
1981 DeLOREAN WORK FINISHED, BUT DeLOREAN EMBEZZELMENT SCANDLE BEGINS.

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AT 4 AM ON THE CHILL DARK
MORNING OF
16 DECEMBER 1982
COLIN CHAPMAN WOULD CROSS
LIFE’S
FINISH LINE,
HIS HEART NO LONGER UP TO THE
PACE…

26. FIVE MINUTES ARE ALLOCATED FOR
ASKING QUESTIONS OF THE AUTHOR
74TH SAWE International Conference on Mass Properties Engineering
Alexandria, VA, 18-22 May 2015 26

27. 74TH SAWE International Conference on Mass Properties Engineering
Alexandria, VA, 18-22 May 2015 27
“Development is the last refuge of an incompetent designer”
Colin Chapman
“Colin was totally uninterested in a car five minutes after it
had been launched. He was a great man for proving that
something could be done, but that was that.”
Graham Arnold, Lotus Cars Sales Director
“Chapman wasn’t very interested in development. He would
find the current situation totally boring. It was new ideas that
kept him going, trying to stay ahead.”
Nigel Bennett, Team Lotus Engineer

28. 74TH SAWE International Conference on Mass Properties Engineering
Alexandria, VA, 18-22 May 2015 28
“I don’t think I want to get involved with engines, I’m not an engine man, really.
Mr. Ferrari himself was an engine man; Carlo Chiti is an engine man; Tony
Vandervell is an engine man, but I am a chassis man, loosely speaking. And I
think good engine men don’t necessarily make good chassis men, and vice versa.
Engine men feel that the way to win races is to get more power from the engine.
That’s what they understand, what they like doing. I’d rather have a nice,
reliable, standard engine just like everybody else and try to build a better
chassis.” Colin Chapman
“Colin really didn’t know anything about engines. I sometimes think he
knew less than me.” Walter Hayes
“He (Colin Chapman) realized that until Lotus created its own engine it
was never going to be recognized fully as a member of the automotive
world.” Mike Warner

29. 74TH SAWE International Conference on Mass Properties Engineering
Alexandria, VA, 18-22 May 2015 29
“We allowed the electrics to be developed on the line by the electrical fitters
that were making the harnesses, fitting the lights. We never actually had a
competent electrical engineer…look at all the various loadings on the
circuitry and design it…We never had what I would call the correct
facilities for doing our own inspection.” Mike Warner, Lotus Q/C
“Engines leaked oil prodigiously. Frames cracked apart in everyday use.
Due to the car’s dense packaging and tiny footprint…service access was
nightmarish. Early Elans flooded when it rained and overheated in traffic,
the Webers leaked fuel directly onto the ignition system, and electrical
problems were legion.” Road & Track
“Lotus engineering is the worst.” Zora Arkus-Duntov
“Lotuses are all rubbish. They always fall apart.” Tony Vandervell

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Alexandria, VA, 18-22 May 2015 30
“Colin’s mind was going 24 hours a day. He was always thinking, always
probing, always asking questions. He was in a category of his own.”
Mario Andretti
“I think of them (concepts) in the bath, and also in the wee small hours of
the morning, lying in bed…I need about five and a half to six hours sleep a
night, and when I’m thinking about something I usually spend an hour or
so just mulling it over.”
Colin Chapman
“I think that progress comes…from a cross-pollination of ideas from other
engineering fields…I like reading on a lot of subjects other than racing…I
get my ideas because I take in…information and design philosophies from
other fields. You got to have a pretty general sort of knowledge.”
Colin Chapman

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Alexandria, VA, 18-22 May 2015 31
“The modern sports/racing car such as the Lotus is designed to be as
light as possible…In this way less power is needed…With less power
the engine is lighter, the transmission is lighter, and the frame that
has to support those components can be made lighter. Lightness can be
said to breed lightness. As opposed to the…vicious cycle we…call this
the ‘benevolent cycle’, and no designer…used this technique with more
success than Colin Chapman.”
Colin Campbell
“I believe in getting light weight from elegance of design rather than
from exotic materials…it isn’t only weight but cost as well.”
Colin Chapman

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Wt = Weight of the vehicle (lb, kg).
g = Gravitational constant, “g” = 32.174 ft/s2.
I1 = Rotational inertia about front axle line (lb-ft2, kg-m2).
I2 = Rotational inertia about the crankshaft axis (lb-ft2, kg-m2).
I3 = Rotational inertia about transmission 3rd motion axis (lb-ft2, kg-m2).
I4 = Rotational inertia about rear axle line (lb-ft2, kg-m2).
TR = Transmission gear ratio (dimensionless).
AR = Axle gear ratio (dimensionless).
RD = Dynamic rolling radius at drive wheels (ft, m).