Due to the Gulf Oil Crisis of the 1970s and more strict emission laws, Porsche like many other car manufacturers at that time, reduced the power output of its naturally aspiratedflat-6 engine to thus creating a huge power and performance gap in its naturally aspirated 911 lineage and the Turbo. Those wanting a model lying in-between that gap had to opt for the expensive and luxurious 928grand tourer. Seeing the potential of the naturally aspirated engine to generate a higher power output while maintaining fuel economy, Ruf introduced the SCR in 1978 based on the 911 SC. This marked the first Ruf modification done to a Porsche 911. Key changes over the 911 SC included an engine with an enlarged capacity of 3,185 cc generating a maximum power output of at 6,000 rpm combined with a special Ruf built gearbox along with a Bosch K-Jetronic fuel injection system and front mounted oil coolers hence achieving the desired fuel efficiency whilst maintaining a higher power output than the donor car. Other aesthetic changes included the "whale tail" spoiler found on the 930 Turbo, a deep chin spoiler at the front, a new front bumper with integrated round brake cooling ducts, optional wide wheel arches as found on the 930 Turbo and special Ruf 5-spoke alloy wheels. The car had a Spartan driver-focused interior with racing bucket seats and six-point racing harness. All of these changes enabled the SCR to achieve identical performance levels as the Turbo. The SCR, with its performance filled the void left between the naturally aspirated 911 models and the Turbo while still costing less than the latter at 65,000 DM. Its publicity in German automobile magazines at the time of its introduction made it a commercial success.
Performance
The SCR could accelerate from in 5.7 seconds, in 23.7 seconds and could attain a top speed of.
Introduced in 2016, the SCR 4.2 embodies the philosophy of the original SCR, delivering high performance from a naturally aspirated engine. The SCR 4.2 utilises the Porsche 993's body-in-white and its multi-link suspension but has extensive use of carbon-fibre in its body work and an integrated roll-cage with the car looking akin to the Porsche 964. The SCR 4.2 utilises the water-cooled "Metzger engine" found in the Porsche 997 GT3 but has its capacity increased to 4.2-litres and its power output increased to and of torque. Power is sent to the rear wheels via a 6-speed manual transmission with limited slip differential, enabling the car to accelerate to from a standstill in 4.1 seconds and on to a top speed of. The interior of the car is driver focused and features the dashboard from the Porsche 993, racing bucket seats with 6-point harness and carbon-fibre, Alcantara and tartan trim. Like the original SCR, the SCR 4.2 features a whale tail rear wing and a front bumper with round brake cooling ducts. The car has a total weight of.
SCR (2018)
At the 2018 Geneva Motor Show, exactly 40 years after the original SCR was introduced, Ruf introduced a new version of the SCR. The new SCR is based on the same principles as the CTR, introduced one year earlier, which includes parts built for the car from scratch. The new SCR has carbon fibre body work, an integrated roll-cage and a 4.0-litre naturally-aspirated flat-6 engine based on the unit found in the Porsche 911 GT3 RS 4.0, generating a maximum power output of and of torque with a red-line of 8,200 rpm. The car has a 6-speed manual transmission directing power to the rear wheels and an in-house developed push-rod suspension system. The optimum combination of power and weight propel the car to a top speed of. The car also has a carbon ceramic braking system for enhanced stopping power, with six-piston calipers at the front and four-piston calipers at the rear. Unlike the original SCR, the new SCR lacks the whale tail wing and features body work akin to the Porsche 964. The car was unveiled in the same shade of green as the original SCR, commemorating 40 years since the SCR's launch.
