Since the beginning, car engineering was a matter of choosing
the right materials and construction to achieve the target -
performance, handling, comfort, space, whatever. Car engineers knew
that no matter how clever they work, there were always compromises. For
example, a chassis designed for good handling must result in
compromised ride quality.
the automotive world was changed in 1987 by Porsche 959. This car
introduced a new concept - Variable. Everything in the car was variable
to suit different conditions of use. Its twin-turbo engine was
variable, using only 1 turbo at low rev and 2 turbos at high rev to
achieve both low lag and high boost. Before that, the size of
turbocharger used to be a compromise between power and drivability. Its
suspensions had variable damping, offering 3 settings to suit different
kinds of road or speed. Similarly, the ride height was also variable.
It can be raised to ride on rough road and lowered on highway to
improve stability and drag. The 4-wheel-drive system was variable, too.
Torque split between front and rear axles can be adjusted to suit
different conditions. When 959 accelerated, initially 80% torque went
to the rear wheels which had most traction due to weight transfer, then
gradually reduced to 60% when acceleration force tailed out. On
slippery surface like gravel or snow, it could be changed to 50:50 to
provide maximum traction.
Variable Technology of 959 foresaw today’s mass production cars. Now
you can see Variable this and that everywhere: variable intake
manifolds (short runners for high speed, long for low speed), variable
valve timing (late timing for low speed, early timing for high speed),
air suspensions (i.e. variable spring rate), adaptive damping, active
anti-roll bars (see BMW 7-series and Citroen’s Activa), active
differential (e.g. Lancer Evo VII), active yaw control (also Evo VII),
ESP stability control, speed-sensitive and variable ratio steering
rack, automatic or sequential gearboxes with sport / comfort / winter
mode, electronic throttle with sport / comfort mode, variable rear
spoiler.... these variable things make cars more versatile. Want
comfort? OK, change the setting of suspension, transmission, throttle
and steering to comfort mode. You even need not to press a button,
because clever electronics already sensed what you want by detecting
your driving style. Once you floor down the throttle, or turn the
steering wheel quickly, the settings will be reverted to sport mode and
you will get tight body control, sharp throttle and gearbox response
while the rear spoiler is raising to generate downforce. So easy,
everybody can drive fast. Whether the driver is Schumacher or Zoo’s
Monkey is not important.
variable technology, chassis engineers became a boring job. Innovative
thinking like Colin Chapman is no longer useful, because variable
technology can largely compensate the inherent flaws of a poor chassis.
Nose heavy? we have active suspensions to reduce nose dive under
braking. High center of gravity? active body control can limit roll to
just a few degrees. What chassis engineers do now is to test their
variable systems repeatedly to sort out the software. That’s a hard but
routine job. In contrast, in the days of Colin Chapman they were more
likely to brainstorm a new chassis concept by sketching with an old
car makers - mostly German - thought they have achieved the impossible
- eliminating compromises, they find their variable systems added
hundreds of kilograms to their cars. A proper Variable performance
saloon weighs about 1700 to 1800kg, so they need to install a bigger
engine. Variable technologies also increases cost by thousands of
pounds, making every new generation more expensive than their
compromise for eliminating compromises.