The anatomy of Ford’s Group B rally
car
Why was the RS200 so different from any, of
Ford before or since? And why was this mid/rear-engine car conceived in the
first place? Like every other Competitive Group B car, the RS200 was always
intended to be a rugged four-wheel-drive machine with the potential for
super-tuning, and one which could be settled quickly, at the side of the road
if necessary, on International rallies. This meant that it was much more of a
`construction set' machine than an integrated model - something that was also
due to the very awkward number of models that had to build for homologation purposes
- 200.
The
anatomy of Ford’s Group B rally car
Unlike every other Group B car, however,
the RS200 was also beautiful, which explains why Ford's design subsidiary,
Ghia, was brought in to advice on the styling at an early stage.
The RS200 was always a compromise design,
not only a car which was as technically up-to- date as Group B regulations
would allow, but one which Ford could make in the numbers which were required,
and one which could also be modified for flat-out competition use, and repaired
at very short notice. Ford, like all its rivals, soon discovered that this was
an extremely difficult brief to satisfy.
As everyone now knows, a change in
motorsport regulations effectively killed off Group B rallying before the end
of 1986. Design updates already in hand would have included the availability of
a 500bhp/2.1 -liter BDT-E engine, carbon-fiber body panels and power-assisted
steering. If only... Turn the page to find out what was under the skin of a
typical production car.
Engine
Developed by Ford Motorsport in conjunction
with JQF Engineering, the turbo charged BDT engine was originally designed for
the Escort RS1700T. Redeveloped for the RS200, it was slightly enlarged to
1803cc, given a dry sump lubrication system, and installed back-to-front in the
engine bay so that the cam-belt and camshaft drive were at the rear. The rather
odd engine size was chosen because an FIA rule applied a multiplication factor
of 1.4 to the capacity of a turbocharged engine, and in this case it put the
RS200 over the 2500cc class limit, and therefore allowed further engine
enlargements to take place for motorsport purposes.
Developed
by Ford Motorsport in conjunction with JQF Engineering, the turbo charged BDT
engine was originally designed for the Escort RS1700T
For installation purposes, the big Garrett
turbo was on the right side of the bay, bolted to the exhaust manifold, the
inlet manifold and throttle body was on the left, the two connected by pipework
and a big air-to-air intercooler mounted at the rear of the body/roof panel.
For higher-output derivatives, extra air
intakes were provided on each side of the intercooler aperture, but these were
not fitted on the basic production line at Shenstone. The basic engine
specification was a 250bhp rating, with boost coming in, rather suddenly, above
3000 rpm, but upgrades, to 300bhp or even 350bhp, were available as after
original production fittings. Other engine fixtures and fittings, such as the
massive dry sump oil tank and the header tank, were bolted up to the sturdy
rear tubular sub-frame which surrounded the engine itself.
Bodyshell
The whole car took shape around a tub which
(in road car form) comprised a complex steel and aluminum honeycomb with a
roof, so shaped that comprehensive roll cage could be hidden away, that twin
fuel tanks could be tucked in behind the seats, and a Sierra windscreen and
cut-down Sierra front doors could be used. Sturdy front and rear tubular
sub-frames were bolted up to the tub, not only supporting the suspension
systems, but also surrounding the engine bay.
The
whole car took shape around a tub which (in road car form) comprised a complex
steel and aluminum honeycomb with a roof
Right from the start, it was engineered to
have a mid/rear-mounted engine which drove forward to a complex
four-wheel-drive transmission mounted between the driver's and passenger's
legs. On the road cars, the body skin panels were made almost entirely of glass
fiber (those moldings were built by Reliant, even though the entire motor car
was not). For practical purposes, and to provide the best possible access to
what they hid, the entire front section was hinged in the nose, the rear
section being hinged from the two-seater cabin. With motorsport practicalities
in mind, both these big moldings were arranged to be easily and quickly removed
from the chassis/tub of the car itself. Though the doors were cut-down Sierra
shapes, they were actually molded in glass fiber.
"unlike
every other group B car, however, the RS200 was also beautiful"
