Founded in the year nineteen twenty-four February 1980

Apart from having to provide an opening in the front
of the car to feed air to the radiator there is the added
drag caused by the air passing through the radiator Reid
Railton was clearly conscious of all this in 1938.
In 1956 when Frank Costin designed the Vanwall
body with 3 very keen eye to drag and frontal area the
opening necessary to pass sufficient air to dissipate the
heat from the 285 b.h.p. engine was remarkable small.
Even so, when the complete car was put in the full-scale
wind-tunnel at RAE Farnborough it was found that the
opening was far greater than was really necessary for
a speed of 150 m.p.h., but of course the Vanwall was
not always travelling at 150 m.p.h. It would have been
interesting to have developed a nose cowl opening like
a camera shutter, that could have opened or closed
automatically as speed varied. For a few seconds at
maximum speed on a straight you could have presented
a totally smooth nose cowling to the air and on hairpin
bends there would have been the maximum opening.
In 1960 when Colin Chapman finally Swallowed
his pride and put the Lotus engine behind the driver, as
John Cooper had been telling him for years, he designed
the Lotus 18 behind the rectangular radiator necessary to
cope with the heat from a 2.5-litre Coventry-Climax four
cylinder engine. The rectangular radiator was the frontal
area permitted for the Lotus 18 design and everything,
apart from the driver’s head, had to be contained behind
that number of square inches. It was not a pretty car, but
it was functional.
The next major trend was to design the radiators
into the sides of the car, on each side of the engine,
saving the weight of water pipes and simplifying the
plumbing, and almost everyone followed this trend
until the Lotus 78 when the radiators were laid almost
fiat within the side-pods and became a vital factor in the
air-flow through and over the car. This is the present
trend, the usual practice being to bleed air off from the
front of the side pod, through the radiators and out over
the top of the side pod. In designing the Williams FW07
Patrick Head went one better and did away with the oil
radiator, thus eliminating the drag caused by radiators
by 50%, for the conventional layout had become to have
a radiator for oil in one side-pod and another for water
in the opposite side-pod. Head replaced his oil radiator
by an enclosed and sealed heat exchanger in which the
oil and water pipes dissipated their heat and distributed
the surplus to each other, the water radiator being the
controlling element. That it worked effectively was
instanced in Austria last year when Alan Jones came into
the Williams caravan after winning the race and said to
Patrick Head, “... the car was perfect. Oil pressure never
wavered, and oil and water temperatures sat at 90°C
throughout ...” That was a designer’s dream come true.
Along the way there have been many variations
and off-shoots and the Porsche designers have been the
bravest, with their air-cooled engines, this system saving
the weight and drag of radiators totally. They reached
their limit with the turbo-charged flat-12-cylinder 917
Can-Am engine, which gave something like 900 b.h.p.
By that time the size of the oil cooler was nearly as big as
a water radiator and could no longer rely on air from the
engine fan to dissipate the heat, so it had to be mounted
at the front of the car. The engine was acting as its own
heat-exchanger between the oil and the air. Development
on the turbo-charged fiat-six 935 series has led Porsche
to use water-cooled cylinder heads, though the cylinder
barrels remain air-cooled.
Gordon Murray attempted to use surface radiators
let into the sides of the Brabham-Alfa Romeo, but he
got his sums wrong and the idea didn’t work. David
Cox developed a brilliant idea for Brabham, where the
radiator was laid fiat on top of the engine and a fan driven
off the back of the gearbox sucked air from under the car,
up through the radiator and out through the fan. As a
cooling system i( was perfect but it transgressed various
aerodynamic parameters laid down by the rule-makers,
so it was banned.
From being a tiresome addition to a racing car, hung
on where best it could be contained, the radiator went
through a period of being the hall-mark of a racing car,
to being hidden away where it would cause least trouble,
to becoming an important part of the overall design; but
it has always been with us and always will he, even if it
is hard to find at times, until someone develops a new
form of heat dissipation or does away with the internal
combustion engine. — D.S.J.
Lotus Register
IN an attempt to draw up an international register of
Lotus owners and their cars. Club Lotus has launched
the Lotus Owners’ Register, membership of which will
be free to all Lotus owners worldwide.
The club is asking all Lotus owners to send their
names, addresses and full details of their Lotus cars to
Club Lotus at the registers offices. Haven House, 22A,
High Street, Watton, Thetford. Norfolk.
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