2008 Porsche RS Spyder

(from Porsche Press Release)  RS Spyder 2008

In order to exploit the scope provided by the LMP2 regulations (Le Mans Prototype 2) to the full, Porsche has completely revamped the RS Spyder. The new design ensures that engine, transmission, chassis, suspension and aerodynamics combine to produce a harmonious overall package. In the interests of optimum driving dynamics, the vehicle concept focuses on the lowest possible centre of gravity, high agility and good traction.

The RS Spyder was the dominant vehicle in the 2007 American Le Mans Series (ALMS), demonstrating outstanding stability and notching up 11 wins in the 12 races, including 8 overall wins.

The RS Spyder has undergone a detailed revamp for the 2008 season. The main focus was on fine-tuning the aerodynamics and the engine. The V8 racing engine developed for long-distance use continues to generate 478 hp with the prescribed air-flow limiter on the basis of a displacement of 3.4 litres. The fuel consumption has been further optimised and the engine has been adapted even more effectively to the E10 fuel containing 10% bioethanol which is required in the ALMS.

The regulations also necessitated additional modifications. As a result of these measures, the LMP2 minimum weight has been increased by 25 kg (ALMS) and 50 kg (LMS and Le Mans) and the tank capacity has been reduced by 10 l for LMS and Le Mans, though not for ALMS.

Technical Description RS Spyder (2008)

Concept
Two-seater, open sports prototype according to A.C.O. Regulations.

Class
LMP2 (Le Mans Prototype 2). Suitable for racing in the ALMS, LMS, other championships
and Le Mans 24 Hour Race.

Bodyshell
Carbon-fibre reinforced monocoque; front, side and rear body sections made of reinforced carbon/kevlar; underbody with skid block (A.C.O.) and rear diffuser; rear wing adjustable on two wing elements; six-point harness with Head And Neck Support System (HANS) modification; fire extinguishing system; helmet protection to FIA and A.C.O. regulations; three-point pneumatic car jack.

Aerodynamics
Variable through rear wing and ride height.

Engine
Eight-cylinder V-engine with 90º cylinder bank angle; watercooled; four valves per cylinder; oil cooling with oil/water heat exchanger; intake system with a 42.9 mm restrictor; intake system with individual throttle butterflies; dry sump lubrication with separate oil tank; Bosch MS 4.2 electronic engine management; sequential multipoint fuel injection.

Capacity:
3,397 cc

Engine output:
Approx 350 kW (476 hp) at 9,800 rpm

Max torque:
Approx 370 Nm (273 lb-ft) at 7,500 rpm

Output per litre:
Approx 103 kW

Fuel grade:
Premium plus (motorsport specification) / E10 racing fuel (ALMS)

Electrical system
Motec display with data memory; 12 V, 26 Ah battery; 140 Ah alternator

Power transmission
Engine and gearbox bolted together to form one drive unit; power conveyed by double joint
shafts to the rear wheels. Manual sequential six-speed dog-shift gearbox, in-line gearshift;
gears shifted electro-pneumatically by way of paddles on the steering wheel; oil/water heat
exchanger; ZF Sachs three-plate carbon-fibre racing clutch; mechanical limited-slip
differential; anti-spin control.

Suspension
Front axle:
Double wishbone track control arm configuration; ZF Sachs four-way gas-pressure dampers, pushrod operation; torsion springs; adjustable anti-roll bar in bending-leaf design; hydraulic power steering with mechanical pump.

Rear axle:
Double wishbone track control arm configuration;
ZF Sachs four-way gas-pressure dampers, pushrod operation; torsion springs; adjustable
anti-roll bar. Overall suspension infinitely adjustable for height, camber, and track.

Brakes
Two-circuit brake system with front/rear split and balance bar control; no ABS; six-piston
aluminium monobloc fixed callipers at the front; cross-drilled, inner-vented carbon brake
discs measuring 380 mm (14.96") in diameter at the front and 355 mm (13.98") at the rear.

Wheels and tyres
Single-piece light-alloy wheels with central bolts
front 12.5 x 18 on 29/65 18 Michelin slicks
rear 13 x 18 on 31/71 18 Michelin slicks

Weight
825 kg (1,709 lb) to A.C.O. regulations
800 kg (1,657 lb) to IMSA regulations

Dimensions
Length 4,650 mm (183.1")
Width 2,000 mm (78.7")
Height 1,068 mm (42.0")

Tank capacity
80-litre (17.6 Imp gal) safety tank with rapid tank filling (LMS/24h Le Mans)
90-litre (19.8 Imp gal) safety tank with rapid tank filling (ALMS)