~ The Lotus Seven
Story ~
Chapter Seventeen
The Series IV - A Seven for the Seventies.
THE SEVENS PLACE IN LOTUS COMPONENTS:
Traditionally Lotus Components, the race car manufacturing arm of the Group
Lotus, had made the Seven to help pay the overheads. Making and selling race
cars meant inconsistent cash flow as the seasonal market for competition cars
meant quiet periods. Compared with the Series Two model, the Series Three had
not been a money earner for the manufacturer, in fact it is said that
Components had lost over £100 on each one sold. Despite this, the model had
still effectively contributed to the overheads.
Mike Warner, the new Chief
Executive of Lotus Components Ltd., had been persuaded to rejoin the group
after a short period ‘doing his own thing’. With Mike came the cast aluminium
wheels which Lotus dubbed ‘Brand Lotus’. Mike’s task was to reduce the losses
that were being made. At the time the other models being produced by the
company included the Type 59 Formula 3 and Type 61 Formula Ford Cars.
SEVEN AGAIN UNDER THREAT:
So again the Seven was
under threat; either production ceased or a version that was cheaper to
produce and more marketable was designed. At an early stage it was decided
that the key to success was going to be cost and volume. The main area where
money could be saved was the aluminium clad tubular chassis being made by Arch
Motors. The Elan chassis made of folded mild steel sheet cost half the money
of the mild steel tubular item made for the Series Three Seven.
The very different Series IV chassis.
A NEW MODEL IS PLANNED:
In the event it was
decided to design an entirely new car. Warner saw that, as far as marketing
was concerned, there were two main areas where inroads could be made. At home
the Seven was to be conceived as Lotuses entry-level car. By making it more
civilised and slightly more roomy, the MG Midget, Austin Healey Sprite,
Triumph Spitfire market could be targeted and the young well-healed drivers of
the day could achieve their desire to drive something different on a daily
basis. In addition the old Series Three Seven had been barred in many foreign
countries as it did not meet with their standards. By tackling these problems
at design stage, a much larger market place was available to the new Seven.
THE GO AHEAD IS GIVEN:
Warner and his design team
consisting of Alan Barrett, Dave Baldwin and Peter Lucas had a model made to ¼
scale which was the subject of a meeting with Colin Chapman. The design was
approved in March 1969 and the team were given the go ahead to produce a
full-size prototype. As cost was the uppermost consideration, there was never
a question that the new body would be made of glassfibre rather than
aluminium.
Factory Photo.
THE NEW DESIGN:
The new body design
consisted of two self-coloured glassfibre mouldings bonded together to form
the outer skin and cockpit and scuttle including the rear wings. This unit was
then bolted to the chassis via bobbins moulded into the glassfibre. A front
hinged bonnet and a pair of re-styled clamshell front wings completed the
bodywork. A Weathershield designed hood with sliding perspex side windows,
albeit still hinged from the windscreen pillars a-la previous models, afforded
much better weather protection.
Peter Lucas’ chassis
design consisted of a simple spaceframe with two steel panels spot-welded to
the engine bay and cockpit sides and a folded pressed steel cross-member over
the centre of the car. To stiffen up the chassis, the glassfibre body also
served to add to it’s torsional rigidity.
RUNNING GEAR:
The new car’s all-Ford
running gear remained mostly unchanged from that of the previous Series Three
model. Ford’s 1300cc and 1600cc Kent ‘crossflow’ engines giving 76 and 84bhp
respectively and the Lotus 1558cc twin-cam unit in Special Equipment 115bhp
and Holbay tuned 125bhp forms. 4-speed gearbox from Ford’s 2000E and rear axle
from the Escort Mexico completed the drive train.
REVISED SUSPENSION:
Whilst using the stronger
axle from the Ford Escort had reduced the problems associated with the Series
Two’s Standard Companion item, there was still a problem. To overcome the
notorious location problems of the previous A-frame arrangement, Peter Lucas
used a pair of Watts linkages and a triangulated arm on the offside to deal
with lateral location.
The front suspension now
had proper double wishbones on each side. Previously the Series One, Two and
Three models had top wishbones which utilised the anti-roll bar as the front
leg. The new parts were similar to those on the Europa model being made from
folded sheet rather than the tubular mild steel used before. Coilspring/damper
units were fitted to all corners of the car as before.
OTHER APPOINTMENTS:
The symmetrical dashboard
was an integral part of the glassfibre body having three sunken panels, two
being for instruments depending on whether the car was left hand or right hand
drive. For the first time more comfortable contoured seats were fitted and
even a hardtop was included as a factory optional extra!
Series IV Factory Announcement.
FROM MODEL TO PROTOTYPE:
Even by the design stage,
Alan Barrett had never driven a Seven before, so he borrowed a metallic blue
Series Three to go home in for the week-end. After the journey he never wanted
to drive it again, he hated it that much, but by the time he had driven it
back to the factory he was beginning to enjoy the experience. Obviously, he
thought, it was an acquired taste! While designing the new car, Peter Lucas
and Alan drove the old Series Three Seven as much as they could in order to
understand the concept, it’s problems and how to improve them. To develop the
chassis a test rig was made consisting of a chassis, running gear, windscreen,
roll hoop and seatbelts to hold the occupants in. This was driven on the
Hethel test track for as much as 200 miles a day. Whilst this was happening
the body design was being finalised. Alan says that the team were left to get
on with the design on their own and without interference from within Lotus or
their dealer, Caterham Car Sales.
PRODUCTION:
The prototype was produced
in just seven months and the new car was launched a short time later in March
1970. With an excellent reception from the motoring press and effective
marketing, production soon climbed to 15 cars per week. In order to be able to
cope with Warner’s projected target of 2000 units a year, chassis production
was given to two contractors; Arch Motors and Griston Engineering. Despite
increasing the number of specialist main dealers from one to five (Caterham
Cars Sales in Surrey, Harrop Motor Company in Cheshire, W. B. Sports Cars in
Bristol, Sprinzels in London for personal export and Lotus Components at the
factory near Norwich.) Warner’s sales figures were infact never to be
achieved. However a £150 profit was maintained from of each car sold.
Price List from later brochure.
DEMISE OF LOTUS
COMPONENTS:
However the small profit
made on each Series IV was not enough to help the ailing ‘Lotus Racing’
(formally Lotus Components) arm of the Lotus Group. Competition, both in terms
of purchase cost and track competitiveness, from builders such as Lola,
Merlin, etc. meant that the market was very different to that a few years
earlier. With heavy stock levels of unsold customer racing cars including some
54 three-year old Formula Fords, it was decided to cease building race cars
for sale and wind-up the company. So after nearly 12 years, it was decided to
move the Seven Series IV production to the Lotus Cars factory where the Elans
were being built.
THE END OF THE SEVEN FOR
LOTUS:
For some time Colin
Chapman had believed that the future of Lotus as a manufacturer of road cars
was to be found in the Ferrari/Porsche ‘supercar’ territory where profits were
much higher. The Seven as a ‘kitcar’ did not fit into this new ‘supercar’
range and in factory built form, with purchase tax paid, it would be too
expensive to be successfully marketed even as an ‘entry-level’ model. The
decision for Lotus to stop production of the Seven was made as early as July
1971, but there was still enough stock of chassis frames for the model to be
made until October 1972. In the event Lotus sold the Series IV Seven, for over
three years, until well into 1973 by which time over 650 cars had been made.
Sources and further reading:
Lotus Seven by Jeremy Coulter (1986/1995)
Lotus Seven Preparation/Restoration/Maintenance by Tony Weale (1991)