New 911 GT3 Cup for the 2005 Motorsport Season

Press Release

The engine: revs? Yes, please!

The engine is the well-known 3.6-litre six-cylinder boxer that has been the base for successful motorsport with near-standard vehicles for the last six years. It is an extremely free-revving unit that develops 294 kW (400 bhp) at 7,300 revolutions per minute in its 2005-spec: an increase of 10hp compared to last year. Maximum torque has grown to 400 Nm at 6,500 revs per minute. The maximum engine speed is 8,200 rpm. An air-collector located under the rear wing uses pressure built up there to supply extra intake air to the engine at high speeds, so that it reaches its maximum power output even more easily.

The forged pistons, the titanium connecting rods, the valves and valve-train feature lightweight technology in design and materials. With the connecting rods and pistons allowing an improved flow of forces to the crankshaft, the engineers were able to dispense with the usual vibration damper on the crankshaft, saving two kilos in rotating masses further enhancing the free-revving performance of the unit.

The basic engine in sandwich design with the cylinder housing, cylinder head and crankshaft housing combined with one another to form one unit for the three cylinders on each side has a very high torsional stiffness. The cylinder liners featured in the light-alloy cylinder housing are made of aluminium and are coated with Nikasil. The cylinder heads, in turn, are made of an extremely temperature-resistant light alloy.

The dry sump lubrication with a separate oil tank ensures an optimum supply of oil to the engine even under extreme acceleration.

The power train: gear shifting at full throttle

After having gained comprehensive experience with sequential gearboxes in international GT championships Porsche now offers this technology to customers in the makes cups, beginning with the Porsche Michelin Supercup in 2005.

The sequential six-speed dog-type 'box of the latest 911 GT3 Cup features a power shift system with ignition cut for very quick upshifting at full throttle. Very close ratios ensure that the engine is used in its optimum rev range with the transmission being considerably shorter than in the road-going 911 GT3 RS. Top speed is reached at approx. 272kph. Thanks to tailor-made gears, a single mass flywheel and the use of a 5.5 inch triple-disc sintered metal clutch, the rotating masses of the transmission are reduced. An oil-water-heat exchanger provides the reliable cooling of the system. Technical Description

Porsche 911 GT3 Cup - 2005

Bodywork

• 997-basis
• Self supporting bodyshell made out of galvanised sheet steel
• Carbon fibre rear lid with adjustable rear wing, rear bumper and doors
• Plastic rear-side and rear windows
• Carbon fibre front bumper and front spoiler edge
• Welded-in steel safety cage
• Racing bucket seat, 6-point safety belt suitable for HANS
• Fire extinguisher system
• 64-litre fuel tank
• Air jack

Engine

• Six-cylinder boxer engine
• 3,598 cc, stroke 76.4 mm, bore 100 mm diameter
• Four valves per cylinder
• 400 hp (294 kW) at 7,300 rpm
• Max. torque 400 Nm at 6,500 rpm
• Max. revs 8,200 pm
• Dry-sump lubrication
• Two-stage resonance intake manifold
• Sequential multi-point fuel injection
• Electronic engine management system MS 3.1
• Two catalytic converters, exhaust system with twin-branch centre exhaust tailpipe
• 98 ROZ Super Plus unleaded

Power Train

• Six-speed sequential dog-type gearbox
• Pressure-oil lubrication
• Gearbox cooling with oil-to-water heat exchanger
• Single-mass flywheel
• Hydraulic clutch centre-release mechanism
• 5.5 inch triple-disc sintered-metal clutch
• Limited slip differential 40/60 percent
• Rear wheel drive

Suspension

• Front: McPherson, blade-type anti-roll bar (adjustable), damper mounted to upright with twin-clamp system
• Rear: multilink, rigid suspended subframe, blade-type anti roll bar (adjustable)
• Front and rear: double coil springs; height, camber and track continuously variable adjustable
• Power steering with elctro-hydraulic pressure feed
• Three-piece central locking aluminium rims
• Front axle: 9J x 18, rim offset 43
• Rear axle: 11J x 18, rim offset 30
• Tyres: Michelin
• Front axle: 24/64-18 (slicks, alternative wet)
• Rear axle: 27/68-18 (wet, alternative wet)

Brake system

• Brake system with adjustable bias bar
• Internally ventilated, perforated PCCB brake discs
• Front 380 mm, six-piston alu-callipers, single piece
• rear 350 mm, four-piston alu-callipers, single piece

Weight

• Approx. 1,150 kgs (incl. oil, coolant)

Price

• 121,500 Euros ex-works, plus VAT