Porsche - 911 RSR (Type 991)

911 RSR (Type 991)

Porsche 911 RSR

The Porsche 911 RSR is a winner: At its first outing at the 2013 Le Mans 24 Hours, the Porsche 911 RSR, which is characterised by a consequent lightweight design and sophisticated aerodynamics, performed brilliantly to ultimately clinch an outstanding double victory. In the Tudor United SportsCar Championship in 2014, it won America’s most prestigious long distance classics in Daytona, Sebring and Petit Le Mans.

The 911 RSR, which has undergone various modifications for the 2015 season, made its debut in 2013 as the predecessor of the successful 911 GT3 RSR. It is based on the seventh generation of the iconic 911 sports car. As with the production vehicle, the wheelbase grew by about ten centimetres. A new wishbone front suspension replaces the previously used McPherson struts. Another new development from Porsche Motorsport is the particularly lightweight racing gearbox. The six gears are selected via paddles on the steering wheel. The 470 hp, four-litre six-cylinder boxer engine was taken from the predecessor and extensively optimised

One of the priorities in the development of the 911 RSR was an evenly balanced weight distribution. The centre of gravity is also significantly lower than that of its predecessor. Carbon fibre played a crucial role in the new design. The front and rear mudguards, front and rear lids, doors, underbody, wheel arches, rear wing, dashboard and centre console are made of the very light and strong material. Moreover, all windows are made of particularly thin and light polycarbonate. Also contributing to the weight reduction is the lightweight lithium-ion battery known from the GT road-legal models.

Better serviceability

The look of the 911 RSR is dominated by the flared mudguards and the deep cooling air intakes at the front. With a new air ducting, the radiator is now centrally-located in the front, which is even more effective than in the previous model. At the same time, the cockpit air-conditioning became more efficient. The quick-change concept of the body parts was specially adapted for endurance racing, allowing for easier maintenance and shorter repair times. The front end, front lid and rear panel are fitted with quick release systems and can be replaced within seconds.

Low positioned static cornering lights provide improved vision and enhanced safety during night driving. The reflective labelling and anti-glare lighting of the control elements in the cockpit ensure optimal legibility in the dark. The arrangement of the switches on the new steering wheel and the pilot-oriented centre console were designed in co-operation with the Porsche works drivers. From the outset, all works drivers took part in the design of the 911 RSR, contributing their vast experience in GT racing.

Numerous improvements

Ongoing improvements have been made on the 911 RSR since its race debut. The revised front end and the new rear wing provide an optimised aerobalance, which allows greater stability in fast corners. Through optimising the front axle kinematics, a more precise steering sensitivity and hence better control of the vehicle in slow and medium speed corners were achieved. The further improved structural stiffness ensures more precise handling. Another new feature is the extensively optimised engine air-intake thanks to improved air filter geometry which contributes to reducing loss of performance due to contaminants. The new FT3 safety fuel tank with a lowered centre of gravity makes it easier to refuel under race conditions.

In order to keep the engineers in the pits up-to-date with all relevant vehicle data, the live telemetry transmits more than 200 different measurements straight to the pit wall stand via an antenna on the roof. Additionally, all data are stored on a memory card onboard the vehicle.

Technical description

Body: Self-supporting body in steel aluminium hybrid design (basis 911 Carrera 4, type 991); welded-in safety cage; removable roof hatch; body widened and aerodynamically optimised with carbon parts; front underbody aerodynamically optimised; PC side and rear windows; adjustable rear wing; steering wheel with shift paddles; six-point safety belt; racing bucket seat; FT3-safety tank with fast filling function; air jack; fire extinguisher.

Engine: Six-cylinder aluminium boxer engine in the rear; bore 102.7 mm; stroke 80.4 mm; capacity 3,996 cm³; power output approx. 345 KW (470 hp) with restrictor; four valve technology; water cooling; dry sump lubrication; multi-point fuel injection; weight optimised modular race exhaust system, twin-branched muffler with centred exhaust pipes.

Transmission: Porsche six-speed sequential dog-type gearbox with pneumatic shift mechanism; oil/water heat exchanger; hydraulic disengagement lever; single mass flywheel; three-plate carbon clutch.

Suspension:
Front axle: Fully adjustable double wishbone; 4-way gas pressure shock absorber; double coil springs (main and helper); adjustable blade-type anti roll bar; power steering.
Rear axle: Multi-link axle with rigidly mounted cross member, adjustable ride height, camber, track; 4-way gas pressure shock absorber; double coil springs (main and helper); adjustable blade-type anti roll bar.

Brake system: Brake system with balance bar control and optimised cooling air ducting.Front: Monobloc six-piston aluminium fixed callipers; steel brake discs internally-vented, 380 mm diameter; racing brake pads.Rear: Monobloc four-piston aluminium fixed callipers; steel brake discs internally-vented, 355 mm diameter; racing brake pads.

Wheels and tyres: Front axle: 12.5J x 18, central bolt, Michelin racing 30/68-18. Rear axle: 14J x 18, central bolt; Michelin racing 31/71-18.

Electrics: Cosworth colour display with integrated data recording and gear shift point display; Cosworth electrical system control; lightweight lithium-ion battery 12 V, 18 Ah; 140 A alternator; air conditioning.

Weight: 1,245 kg (minimum weight in compliance with regulations).