The modified BMW Z4 GT3 completes test run


The modified BMW Z4 GT3 has survived its baptism of fire: the GT customer sports car proved itself in a series of intensive tests in recent weeks. The goal of the latest modifications was primarily to improve aerodynamic efficiency in order to ensure the car's competitiveness in the many, hard-fought GT3 classes.

The BMW Z4 GT3, which was launched in March 2010, achieved its greatest success to date in January 2011. Claudia Hürtgen (DE), BMW works driver Augusto Farfus (BR), Tommy Milner (US) and Edward Sandstorm (SE) won the Dubai 24 Hours for Team Schubert. This was the first outright victory for the BMW Z4 GT3 at a marathon race of this scale, having already proven its potential with wins in its debut season in the FIA GT3 European Championship.

With its elongated bonnet, the driver’s compartment towards the rear of the car, long wheel base and narrow wheel arches, the series version of the BMW Z4 boasts an unmistakable appearance. The two-seater provided BMW Motorsport engineers with a good basis for developing a competitive GT3 racing car.

A difference between the production and racing car can be found under the bonnet: while the production version of the BMW Z4 is driven by a six-cylinder engine, the GT3 car is powered by a 4.4-litre eight-cylinder engine.

BMW Motorsport engineers have also fine-tuned the aerodynamics of the BMW Z4 GT3 for the new season, improving the car's performance in this area. When it comes to electronics, the private teams can look forward to innovative BMW solutions: The modern ECU408 takes over the engine management, while the Power400 electronic control unit is responsible for controlling all the actuators. The power is transmitted through a six-speed, sequential gearbox. Gearshifts are now initiated using two paddles.

The steel body of the car comes from BMW Plant Regensburg. A safety cell made of extremely rigid, precision steel tubing is then welded into the body. The engine block of the V8 engine is produced in the BMW foundry in Landshut. BMW Plant Dingolfing contributes the rear axle differential, among other things. Front and rear wings, bonnet, roof, fenders and many other components are made of carbon fiber reinforced plastics (CFRP).

The car is available now at a price of 315,000 Euros (plus VAT) from BMW Motorsport Distribution, email address Z4GT3@bmw-motorsport.com.

BMW Z4 GT3 – Technical specifications.

Width:2,010mm

Height:1,210mm

Wheel base: 2,510mm

Tank capacity: 100 liters

Price:315,000 Euros (excl. VAT)

Chassis/body:Unitary construction steel body with welded safety cell made of extremely rigid, precision steel tubing, safety fuel tank in CFRP sandwich tray, pneumatic four-stamp jack system

Aerodynamics:Front wings, rear apron, bonnet, roof, boot lid, rocker panel, doors, front wings and flared rear wheel arches made of carbon fiber, rear wing made of aluminum compound

Transmission:Sinter clutch operated by hydraulic central slave cylinder; six-speed sequential racing transmission with straight-cut, unsynchronized gears; additional oil/air cooler; quick shift system with ignition cut-out controlled by shifting force; mechanical differential lock and additional oil/air cooler

Front axle: Double-joint thrust bar axle, with increased wheel caster angle, enlarged track width and enhanced wheel camber compared to production version; five-way adjustable shock absorbers; tubular stabilizer bar

Rear axle: Longitudinal link axle with two transverse control arms, with enlarged track width and enhanced wheel camber compared to production version; five-way adjustable shock absorbers, tubular stabilizer bar

Front brake system: Six-piston aluminum brake calipers, inner-vented grey-cast iron brake disks 378 mm in diameter

Rear brake system: Four-piston aluminum brake calipers, grey-cast iron brake disk, 332 mm in diameter

Steering:Rack and pinion steering with electro-hydraulic power

Wheels:Aluminum rims, front axle: 12×18 inches, rear axle: 13×18 inches

Cockpit:Free programmable LCD Display with integrated shift indicators

Steering wheel: Quick release multi-function steering wheel with integrated display unit; integrated shifting paddle

Energy management: Electric energy management and monitoring with BMW Motorsport POWER400 control unit, networking through two bus systems

Engine type: Eight-cylinder, V-configuration

Capacity:4,361cc

Bore x stroke: 92x82mm

Max. engine speed: 8,500rpm

Cylinder block: Aluminum cylinder block construction with bed plate lower section

Crankshaft:Steel crankshaft

Pistons:Forged skirt pistons

Conrods:High-performance steel

Cylinder head: Aluminum DOHC (Double Over Head Camshaft); four valves per cylinder

Valve train: Four overhead chain-driven camshafts, valve actuation via rocker arms

Intake system: Eight throttle valves

Exhaust system: High-performance header, silencer

Fuel system: Single cylinder multi-point injection

Lubrication: Dry sump lubrication

Cooling: Water/air cooler and oil/water heat exchanger

Engine management: BMW Motorsport ECU408 with two high-performance micro-processors; individual cylinder injection; pit speed limiter; quick Shift function; EML; integrated traction control; VANOS control; engine data memory system

Wiring harness: Weight-optimized

Ignition coil: Eight high-performance pencil coils with integrated ignition drivers

Spark plugs: High-performance spark plugs