Local News: R8 GT now available

Even lighter, more powerful and faster – the Audi R8 GT is the exclusive top-of-the-line model of the R8 family, a driving machine with breathtaking acceleration and power. Only 333 units will be hand-assembled for delivery to markets worldwide. Singapore has been allocated five units.

The R8 high-performance sports car has been a winner from the very beginning, garnering awards such as the “World Performance Car” accolade in 2008 (R8) and in 2010 (R8 V10). The R8 LMS also won 23 races in its first season and claimed three championships. Now, the genes of the race version are coming to the streets of Singapore in the form of the Audi R8 GT.

Compared to the R8 5.2 FSI, the output of the Audi R8 GT’s 5.2-litre V10 has been increased to 560 bhp while its vehicle weight has been reduced by roughly 100 kg. With quattro (and without a driver), the Audi R8 GT tips the scales at just 1,525 kg, for a power-to-weight ratio of only 2.72 kg per bhp. In addition to the aluminium Audi Space Frame (ASF) body, new components made of carbon fibre composite contribute to the low weight of the high-performance sports car. The R8 GT is also faster and more efficient – it accelerates from zero to 100 km/h in 3.6 seconds and reaches a top speed of 320 km/h.

The design of the Audi R8 GT combines highly-concentrated power and a technical sculpture. The dimensions allude to the contours of the vehicle’s dynamics – 4.43 metres long, wheelbase of 2.65 metres, 1.93 metres wide, and only 1.24 metres tall.

Audi designers have made numerous modifications to the exterior, many of which serve to lower the weight and further improve the aerodynamics. For example, the R8 GT produces even more downforce when driven fast than the production model, without any increase in the Cd value of 0.36 or frontal area of 1.99 square metres.

The frame of the single-frame grille, its struts and the slats in the air intakes are matte titanium grey; the grille is painted matte black. The front splitter under the bumper has a double lip and is made of a carbon fibre composite (CFRP). Curved flics made of CFRP at the corners of the nose increase the downforce on the front axle.
One characteristic highlight of the Audi R8 GT is the standard LED headlights. They produce bright, homogeneous light, have a long service life and low energy consumption. The headlights also give the new top model of the R8 line an unmistakable look, day or night. The reflectors are reminiscent of open mussel shells; the daytime running lights each comprise 24 LEDs and appear as a continuous band.
The side view of the R8 GT is dominated by the sideblades made of matte CFRP too, which directs air to the engine. The same material is used for the side mirrors with the LED turn signals. The housings are mounted on an aluminium base with broken-out slats. Audi has developed an exclusive five twin-spoke Y design in a titanium-look finish for the 19-inch wheels. The front fenders bear R8 GT badges, and the sill extensions have been widened.

The modifications to the rear of the car particularly stand out. The fixed wing of matte CFRP is mounted to the body with two bars and saves 1.2 kg of weight compared to the R8 5.2 FSI quattro. The ventilation louvers on both sides of the long rear hatch have been redesigned, as has the CFRP bumper, which frames the large, round tailpipes and vents for the wheel wells.

The larger diffuser is also made of CFRP; the license plate bezel and the wide slats at the rear are finished in matte titanium grey. The taillights, also with LED technology, have dark housings with panes of clear glass. The R8 GT is available in four body colors: Samoa Orange, metallic; Ice Silver, metallic; and Phantom Black, pearl effect; Suzuka Gray, matte is available as an option.

The car on which the Audi R8 GT is based – the R8 5.2 FSI quattro – adheres strictly to Audi’s lightweight construction philosophy, weighing just 1,525 kg with the standard quattro drive (without the driver). In keeping with ASF technology, its body is made of aluminium. Cast nodes and extruded sections form a very high-strength frame, to which the aluminium body panels are joined by positive and friction connections. Ultra lightweight magnesium is used as the material for the engine frame.

The space frame body, which is largely hand-built in a complex fabrication process at the Neckarsulm site, weighs only 210 kg. The windshield of the R8 GT is made of thinner glass. The bulkhead between the passenger cell and the engine compartment is made of a strong, lightweight polycarbonate, as is the window in the rear hatch that allows the V10 engine to be seen in all its technical glory. These three modifications amount to a weight reduction of nine kg. Thinner sheet metal and additional cutouts shave 2.6 kg from the aluminium hatch over the 100-litre luggage compartment at the front of the car.

The rear hatch of the R8 GT also contributes to the weight reduction. It is a self- supporting structure made of CFRP – an advantage of 6.6 kg. The rear bumper and the sideblades of this same material save an additional 5.2 and 1.5 kg respectively.

Audi has also gone to great lengths to save weight in the interior. The new, lightweight carpeting saves 7.9 kg; the bucket seats with a chassis of glass fibre- reinforced plastic (GFRP) account for 31.5 kg of reduction.

The redesigned selector lever, which bears the serial number of the individual R8 GT, is made of CFRP and aluminium. The “monoposto”, the large arch around the ergonomically perfect and spacious cockpit, is made of matte CFRP.

In true Audi style, the interior shows great attention to detail. Rich materials treat the occupants to a fine look and feel. Sporty black and dark grey hues dominate. The sport steering wheel with the flat- bottomed rim, the headliner, the roof posts, the knee pad, the handbrake lever and the bucket seats are covered with Alcantara accented with contrasting stitching.

The V10 powers the Audi R8 GT like a race car. The sprint from zero to 100 km/h takes 3.6 seconds; from zero to 200 km/h only 10.8 seconds. Acceleration remains brisk until the top speed of 320 km/h is reached.

Enhancements to the engine electronics coaxed an additional 35 bhp from the V10, which now produces 560 bhp at 8,000 rpm from a displacement of 5,204 cc. The engine is electronically limited at 8,700 rpm. The torque curve peaks at 540 Nm at 6,500 rpm, 10 Nm more than in the R8 5.2 FSI. The R8 GT boasts 107.6 bhp per litre of displacement, and a power-to-weight ratio of only 2.72 kg per bhp.
Among the characteristic features of the V10 is the cylinder angle of 90 degrees, which lowers the center of gravity. Dry sump lubrication allows the engine to be installed low. Its highly efficient pump module ensures that the 40-valve engine is lubricated even under extreme lateral acceleration.

The long-stroke engine weighs only 258 kg. It features a crankcase made of an aluminium-silicon alloy that is both lightweight and very strong. The high silicon content makes the cylinder barrels extremely durable. The bedplate – a stable frame for the crankshaft bearing bridges – further enhances the block’s rigidity.

The crankshaft is designed as a common pin shaft in order to combine maximum rigidity with minimal weight. The connecting rods of the opposing pistons engage a common crankpin, resulting in alternating firing intervals of 54 and 90 degrees.

This unique rhythm gives the V10 its fascinating sound with increasing revs, with a powerful bass foundation and sharp overtones. Two flaps in the exhaust system modulate its volume and tone as a function of load and engine speed.

The powerful, normally-aspirated engine consumes an average of 13.9 litres of fuel per 100 km. The FSI gasoline direct injection system injects the fuel into the combustion chambers at up to 120 bar of pressure. Thanks to the internal cooling, this allows a high compression ratio of 12.5:1, which once again benefits efficiency. Tumble flaps in the intake ports optimise the filling of the combustion chambers by inducing a tumbling motion in the inflowing air. The camshafts, as well as the oil pump, water pump and parts of the auxiliaries, are powered by maintenance-free chains located on the rear wall of the engine. This design principle is an exclusive feature of the V8 and V10 engines that accounts for much of the compactness of the drivetrain. The induction pipe is made of lightweight plastic, designed for optimised flow conditions through the ports.

Audi has also rigorously shaved weight from other engine-related components. The engineers found 9.4 kg in the battery, 2.3 kg in the air intake module and 2.8 kg in the insulation of the engine compartment. This was accompanied by a variety of other measures, such as the use of lightweight steel for the exhaust tailpipe trims.

The Audi R8 GT has the R tronic on board, which can be controlled via paddles on the steering wheel. The automated manual transmission offers the advantages of a manual gearbox – high efficiency, compact dimensions and low weight – but changes gears much faster than any driver could.

The speed at which the R tronic works varies as a function of engine speed and the shift program. Two manual and two fully automatic modes are available. At high load and revs, gear changes take only around one-tenth of a second.

Driver’s commands are transmitted electronically to the switching unit of the R tronic. Powered by an electric pump, its hydraulic fluid system provides the required pressure of 40 to 50 bar. The hydraulics actuates the clutch, which at only 215 mm, is very compact. This compactness is necessary because of the low installation position of the R8 engines. Gear changes are performed with the help of a second hydraulic block.

The R tronic also features the “Launch Control” program, which enables the R8 GT to spring into action in spectacular style. It modulates the throttle valves in conjunction with the engagement of the clutch at high startup revs so that the engine’s power is delivered to the road with minimal wheel slip.

With its longitudinally mounted mid-engine, the Audi R8 GT has a weight distribution of 43:57, and its quattro powertrain accordingly sends a majority of the power to the rear axle. The transmission is located behind the V10, and it includes an auxiliary drive for a prop shaft running below the engine to the front axle, where a viscous coupling distributes the power. In regular operation, it diverts roughly 15 per cent of the torque to the front axle and can send up to an additional 15 per cent to the front extremely quickly if the rear wheels begin to slip.

The primary component of the viscous coupling is a package of round clutch disks that rotate in a viscous liquid. If they rotate at greatly different speeds due to decreasing traction at the rear axle, the oil becomes more viscous as a result of its internal friction and increased torque is delivered to the front axle. A mechanically locking differential at the rear axle further improves traction. It provides up to 25 per cent lockup when accelerating and up to 40 per cent on the overrun.

The handling of the Audi R8 GT is pure joy. Its engine is mid-mounted close to the vertical axis; its mass is almost negligible during fast direction changes. As such, the high-performance sports car is dynamic, highly precise and stable in every situation.

Audi follows the classic racing design when it comes to the suspension – double wishbones made of aluminium locate the wheels. The hydraulic, power-assisted rack- and-pinion steering has a direct 16.3:1 ratio for a sensitive connection between the driver and the road. The optimally-tuned coilover suspension lowers the vehicle body by as much as 10 mm. Higher front and rear wheel camber rates make the handling slightly more agile than with the standard model.

The top-of-the-line R8 model rolls out on 19-inch forged wheels. They measure 8.5 J x 19 at the front and 11 J x 19 at the rear, with 235/35 and 295/30 tyres, respectively. A tyre pressure indicator is standard. 305/30 tyres are available at the rear in conjunction with the range of optional wheels. For racing enthusiasts, Audi offers sport tyres that provide the ultimate in performance on dry roads. Because extreme power requires superb control, internally vented and drilled brake discs of carbon fibre ceramic are mounted behind the large wheels of the R8 GT.

The ESP stabilisation program can be switched into a Sport mode at the push of a button to allow fun, but safe, oversteer when accelerating out of a corner. The driver can deactivate the system entirely for a trip to the race track.

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