The Sports Car: Its design and performance

315 Pages·1978·10.385 MB·English

by  Colin Campbell M.Sc., C.Eng., M.I.Mech.E. (auth.)

THE SPORTS CAR
THE
S P O R T S
CAR
Its design and performance
COLIN CAMPBELL
M.Sc., C.Eng., M.I.Mech.E.
CHAPMAN AND HALL
LONDON
First published 1954
Reprinted (three times) 1955, 1956
Second edition 1959
Reprinted 1960, 1961, 1962, 1965
Third edition (revised) 1969
Fourth edition 1978
© Colin Campbell 1959, 1969, 1978
Softcover reprint of the hardcover 4th edition 1978
Photoset in English Times by
Red Lion Setters, Hotborn, London
ISBN-13:978-1-4613-3386-9 e-ISBN-13:978-1-4613-3384-5
001: 10.1007/978-1-4613-3384-5
All rights reserved. No part of this book may be
reprinted, or reproduced or utilized in any form
or by any electronic, mechanical or other
means, now known or hereafter invented,
including photocopying and recording, or in
any information storage and retrieval system,
without permission in writing from the
Publishers.
To my wife
for her toleration of much fast motoring
and more slow writing
Preface to fourth edition
Preface to fourth edition
Some of the sports cars I wrote about a quarter of a century ago are still with us.
I saw a few of them at the 1977 BARC Easter Monday meeting as they fought it
out so valiantly over ten laps of the Thruxton circuit in the Classic Sports Car
Race. It is a sobering thought that many of the readers of this new edition were
not even born when I first attempted to analyse the technical make-up of such
wonderful sports cars as the XK120, the Aston Martin DB2 and the Austin
Healey'Hundred'.
The greatest upheaval on the technical scene in recent years has been the
challenge thrown out by government legislation around the world to increase
safety and to reduce pollution. The former has virtually wiped out open-air
motoring in several countries with warm climates, which is a pity. The latter has
made it illegal in some countries for the enthusiast to tune his own car. This new
edition therefore contains no advice on tuning, since this must now be
considered as a professional prerogative demanding sophisticated and expensive
instrumentation.
Apart from a general up-dating of all the subject matter we have added four
design studies, partly historical, partly technical, on the Jaguar, the Lotus, the
Mercedes and the Porsche. The author is particularly indebted to these four
companies for their assistance in providing so much useful technical informa
tion on their products.
Grateful acknowledgement is also given to the many sports-car manufacturers
who supplied technical data, drawings, photographs and handbooks, and to all
the other component and specialist equipment manufacturers who gave such
valuable assistance.
The question of units for this new edition is a difficult one. Great Britain, in
viii The Sports Car
theory at least, is now using metric (SI) units. Power should be expressed in
kilowatts, torque in newton metres and speed in metres per second. Not only is
the British motor industry reluctant to make the change, but the majority of our
English speaking readers are in America, Canada and Australia where metric
units are only used by scientists. In general in this edition we have given
quantities in both SI units and in foot-pound-second units. There are excep
tions. Motorists still prefer to think of speed in terms of miles per hour or
kilometers per hour and engine speed will be quoted in terms of r. p.m. for many
years to come. Eventually we shall become accustomed to saying that 'James
Hunt wrecked his engine by using too many radians per second.' I do not think
that 'Master James' will ever express it in such terms.
Suffolk C.C.
July, 1977
Contents
Preface to Fourth Edition page vii
Chapter 1 The Development of the Sports Car
Motor sport . The sports car . The history of the sports car . The
first sports car . The fabulous years . Historic sports cars . The
future of the sports car.
Chapter 2 The Engine: Combustion 18
Cylinder head history . Combustion chamber research .
Volumetric efficiency . Knock . Limiting compression ratio .
Types of combustion chamber.
Chapter 3 The Engine: Induction and Exhaust 35
The induction system . The 4-cylinder in-line engine. The
6-cylinder in-line engine. The V-8 engine. Ramming induction
pipes . Ramming pipe theory. Forward-ram intakes. Cold-air
intakes . The exhaust system . The silencer . Ramming exhaust
pipes. Branched exhaust pipes.
Chapter4 The Engine: Valve Gear 55
Push-rod valve operation. Double overhead valve operation.
Single overhead camshaft head . The four-valve head .
Desmodromic operation.
x The Sports Car
Chapter 5 The Engine: Fuel Metering 67
The carburettor . The S.U. principle. The H.I.F. model. Fuel
injection. Lucas electronic fuel injection. Bosch K-Jetronic
mechanical system.
Chapter 6 The Engine: Miscellaneous Components 82
The crankcase. The crankshaft. Crankshaft bearings: bearing
pressures: bearing materials. General lubrication . Pistons.
Cooling: air cooling: water cooling . The ignition system: sparking
plugs: the conventional coil ignition: new ignition developments.
Chapter 7 Road-Holding 112
Tyres: the grip on the road: the tyre footprint. Cornering power.
Tyre construction . Aquaplaning . Cornering behaviour: oversteer
and understeer: rear wheel drive: front wheel drive: braking . The
mid-engined sports car . Factors leading to understeer.
Chapter 8 The Suspension 140
Springs . Pitching . Independent suspension . Shimmy and tramp .
Representative designs: Jaguar, Porsche, Datsun, Aston Martin.
The suspension damper: double-tube damper: single tube damper.
Chapter 9 The Chassis, Frame and Body 169
Materials . Torsional stiffness . The tubular frame . Unitary body
chassis construction . The backbone chassis . The shape of the
body: drag coefficients, lift at high speed, the air dam, directional
stability at high speed.
Chapter 10 The Transmission 186
Torque multiplication . The gear ratios . The overdrive . Synchro-
mesh . The automatic transmission . The clutch . The final drive .
Universal joints. The limited slip differential.
Chapter 11 The Brakes 200
The grip on the road. Braking forces. Weight transference under
braking. Brake fade. Disc brakes: disc brakes for the high-speed
sports car, pad materials.
Chapter 12 .Performance 211
Standards of performance . The meaning of power . Acceleration:
acceleration times for 0-60 m.p.h., the concept of effective mass.
Maximum speed.
Contents xi
Chapter 13 The Sports Car in the Future 223
The Engine: promising alternatives, the gas turbine, rotating
combustion engines, the Diesel engine, the Stirling engine, the
steam engine. Petrol engine developments: stratified charge:
turbocharging: air fuel ratio control . The transmission . Tyres
and suspension: no-roll suspension . Braking. The long-life car.
Chapter 14 Design Studies 250
The Jaguar
The Lotus
The Mercedes
The Porsche
Index 302
The development
of the sports car
'We are living in a time when
the plural is killing the singular;
nothing has real value
when everything comes in thousands.'
JEAN COCTEAU
Motor sport
Man is an adventurous and fun-loving creature. If we can bring ourselves to
accept that we are descended from some branch of the monkey family, it is no
longer difficult to understand that our boldness and our love of fun are
instinctive. Our instincts are sometimes strong enough to break through that
polished skin of sophisticated behaviour that we call civilized living, strong
enough to make us do the most irrational things in the name of sport.
Nothing could be more serious than transport. Our modern suburban life
would break down without it, yet we cannot resist any opportunity to create fun
and sport out of this transport, whatever form it may take. Horse racing was
inevitable, chariot racing irresistible and to those of us with muscles and wind
enough the invention of the penny-farthing bicycle became just another thing to
be raced. Who can tell what the next generation will do with space vehicles!
Motor sport is our immediate concern and with this particular form of
transport we have given wide range to our faculty for invention. Not content
with racing it round and about and up and down, we invent all manner of games
of skill and chance, trials, rallies, gymkhanas, auto-cross, scavenge hunts and
treasure hunts.
Sport and danger are often inseparable. Sometimes we seem to go out of our
way to ensure this. The writer was a little horrified when he saw that the
Kentucky Auto Speed Championship was to be fought out with old stock cars
fitted with souped-up engines around a figure-of-eight course. The centre of the
circuit was thus an uncontrolled crossroads to be negotiated at speeds approaching
60 m.p.h. with a field that soon became spread out, not only around the course,
but on all sides of the cross-roads. If racing improves the breed, the future
Kentuckians will be happy in the cut and thrust of modern traffic.