Year: 1990 | Generation: 964 | Units built: 22
Engine: 3.6L Air-cooled Flat-6 | Power: 300 bhp | 0 – 60 mph: 4.9 s | Top Speed: 161.59 mph
A handful of specially prepared lightweight 911s were fabricated by the Porsche factory and called the Carrera 4 RS Lightweight. Built by Porsche’s customer motorsport division, the Porsche 964 Carrera 4 Lightweight programmed was Jürgen Barth’s way of keeping his department employed in the wake of Group C’s collapse.
130kg lighter than a 964 RS, the Carrera 4 Lightweight used the four-wheel drive drivetrain from the Dakar-winning 953 rally car and was originally envisaged for off-road use. The cars employed the same six-cylinder 3600cc boxer engine as the 260hp “regular” RS but produced some 40 more horsepower due to the exclusion of catalytic converters and mufflers.
The RS Lightweight earned its name thanks to the combined use of an aluminum front lid, aluminum doors, Plexiglas side windows and a fiberglass rear engine lid. Its overall weight was pared down to 1100kg (2200 lbs) thus making for an exceptional power to weight ratio. For those keeping count that is 350kg (770 lbs) lighter than standard 964 C4. They also added a short ratio 5-speed transmission with lightweight flywheel.
The list of weight reduction features included an aluminum safety cage, two Recaro race seats with five-point safety belts, sport steering wheel coupled to a power assisted steering rack and a type 953 Paris-Dakar transmission. The doors and front hood replaced with aluminum versions and side window glass replaced with plexiglass. Carpeting and sound deadening was removed and left as bare metal.