Subaru, part of the Japanese Fuji Heavy Industries, is a relative newcomer to the World Rally Championship. Nevertheless its grip is firmly set on the FIA. The company managed to push the WRC class car regulations on Max Mosley (president of the FIA) and got hold of all major decision makers in the WRC. Subaru's marketing strategy is enormously focused on rallying. That fact constitutes an excellent basis to put in place the world's best rallying team using some of the best drivers, advanced technologies and cars today. The Subaru Imprezas are prepared for competition at Prodrive's plant in England. Prodrive is an extremely professional and well managed team (lead by David Richards). Their drivers for the 1999/2000 seasons are:
Most WRC events are run on slippery surfaces so Prodrive's choice of drivers that perform best on this type of surface seems logical. But enough politics lets see what the car is like. There is no special history behind the Impreza. The car was chosen as a potential WRC champion mainly because it was smaller (lower inertia) than the Legacy, its predecessor. Subaru clearly wanted to be world champion so they put a lot of hard work into the Impreza, Prodrive took on from there to lead the car to the world title. Launched in 1994 the Impreza was immediately available in a 4 wheel drive turbo charged version delivering 211Bhp (217Bhp for the 1999 European model). The car's main peculiarity is its engine. It's a 4 cylinder boxer, all aluminum construction mounted longitudinally at the front. Boxer engines have the advantage of lowering the center of gravity of the whole structure. In the Impreza's case things got quite complicated due to the fact that the engine is turbocharged. The intake tubes are on the upper part of the engine while the exhaust tubes are, partly, on the lower part. The turbo charger is mounted on the right side of the engine. Mounting the turbo this way is quite new and certainly one of the many achievements of Subaru in the Impreza. Since the exhaust tubes use significantly different lengths to reach the turbo charger it is relatively difficult to assure a constant charge of the compressor wheel. The biggest drawback of the Impreza boxer engine is the proximity of the inlet manifold to most heat sources in the engine bay. Additionally the intercooler is located above the engine, which is definitely not the best place to put it, hence the big central air vent on the bonnet. A similar choice, for the intercooler placement, in the Nissan Sunny GTi-R of old resulted in engineers calling it inter-warmer...Locating the intercooler this way results in relatively high intake air temperatures of around 50 °C and thus reduces the engine's efficiency. The racing version of the Impreza uses an intercooler which is relocated in the front bumper. The engine being mounted longitudinally, the gearbox and transmission are much easier to fit and service than they would have been in a transversally mounted engine configuration (like in the Lancia Integrale or the Toyota Celica GT4 and Corolla WRC for instance). Speaking of transmission nothing but classic things here in the street Impreza version. Free differential in the front axle (like most other 4WD turbocharged cars with the exception of the Mitsubishi Lancer Evolution V and VI), viscous coupler in the central epicyclical differential while a second viscous coupler is fitted in the rear differential. The street version of the Impreza has three major drawbacks: low performance tires, an imprecise, slow gearbox (dating 30 years back to the original Subaru design) and too much steering wheel travel from lock to lock. While the first is easy to correct (you'll have to fit 16" or 17" wheels and performance tires, note that since 1998 the Impreza turbo uses 16" wheels but is still fitted with low performance tires) the second and third ones are a pain in the back. Kits are available to shorten the gear-lever travel while mounting the whole lever structure on Teflon cushions (quick-shift). There are no kits to improve on the too low ratio steering however. These modifications done (plus a suspension and injection chip upgrade resulting in a total of 240Bhp or more, at the expense of overall reliability) the street Impreza is a very fast car. I'll state the English magazine CAR which tested the (modified) Impreza on track some years ago and declared: "If you can't drive this car fast you can't drive fast." I think that says it all.
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