Re: Audi to launch TT TDI
The new Audi TT 2.0 TDI quattro: owerful performance with maximum efficiency
Audi is once again setting standards, this time with the new Audi TT and its TDI engine—a model that combines pure sportiness and powerful performance with sensational efficiency. The Audi TT 2.0 TDI Coupe quattro and Audi TT Roadster 2.0 TDI quattro are the first series-production sports cars to feature diesel engines. It’s a compelling union: the two-liter engine generates dynamic propulsion with 125 kW (170 hp) and 350 Nm (258.15 lb-ft) of torque, yet the TT Coupe and TT Roadster consume an average of only 5.3 liters and 5.5 liters of fuel per 100 km (44.38 mpg and 42.77 mpg) respectively—unparalleled in the sports car segment.
Audi is setting the pace with this synthesis of excellent dynamism and low fuel consumption, as it has done for many years: Since debuting in 1989 the TDI engines from the brand with the four rings have been paving the way for the world’s most successful efficiency technology and acting as trendsetters for the entire automobile industry. Today, these powerful, refined and highly fuel-efficient engines represent a modern, smart take on sportiness. The run of victories achieved by the Audi R10 TDI diesel race car at the Le Mans 24 Hours and in the American Le Mans Series are impressive evidence of the tremendous potential of this technology.
The dynamic diesel engines from Audi exert an exciting impact not just in racing but also in series-production models—and now indeed in a sports car. The TT Coupe quattro with the 2.0 TDI sprints from zero to 100 km/h (62.14 mph) in 7.5 seconds and achieves a top speed of 226 km/h (140.43 mph). The Audi TT Roadster, likewise equipped with quattro permanent all-wheel drive, requires only an extra tenth of a second for the standard sprint, and continues up to a top speed of 223 km/h (138.57 mph). Both versions serve as outstanding examples of the success of the Audi efficiency strategy, thanks to their fuel efficiency ratings of 5.5 liters per 100 km (42.77 mpg), a figure that corresponds to CO2 emissions of only 145 grams/km.
Powerful, refined and efficient: The 2.0 TDI
The new four-cylinder TDI engine (engine displacement = 1,968 cc) represents a fresh take on the all-round compelling qualities of the TDI concept. Designers of the dual-camshaft, two-liter model looked to its predecessor—the most-produced diesel engine in the world—and expanded upon its major strengths: driving pleasure, efficiency and refinement.
The new common rail injection system is equipped with highly modern piezo injectors, whose eight-hole injection nozzles can perform up to five distinct injection sequences per cycle. This fine degree of modulation creates a modest pressure increase in the combustion chambers, resulting in a significantly reduced noise level. The system pressure of 1,800 bar allows fuel to form a fine dispersion, enabling precise, highly efficient combustion.
The turbocharger is also part of a new generation and operates with adjustable vanes that allow torque to build up rapidly. The positions of swirl flaps on the intake manifold are controlled by electric motors in order to adapt the flow of air to the current load and engine speed. The geometry of the engine’s pistons has been modified, and the acoustics of the camshaft drive belt have been overhauled. Just as they did in the preceding model, two balancing shafts reduce the vibrations arising in the crankshaft drive.
The cumulative result of this progress is a high maximum engine speed of 5,000 rpm and, most importantly, improved thermodynamics in the combustion chambers. What this means is that the engine can run on up to 60 percent recycled exhaust that has been thoroughly cooled by the radiator. This results in a drastic reduction in untreated NOx emissions, with the 2.0 TDI already meeting the threshold values of the upcoming Euro 5 standard.
Dynamic road performance
The 2.0 TDI in the Audi TT Coupe and the Audi TT Roadster delivers 125 kW (170 hp) at 4,200 rpm and sends a full 350 Nm (258.15 lb-ft) of torque to the crankshaft at engine speeds between 1,750 and 2,500 rpm. Operating quietly and generating little in the way of vibration, this model delivers a hefty amount of power at the lowest rpm levels and is highly responsive to input from the gas pedal. Its supreme power development lends this engine its own unique, fascinating character—that of a muscular, smart sports engine.
The Audi TT Coupe 2.0 TDI quattro easily leaves the gasoline-powered competition behind when accelerating from a standstill. It sprints from zero to 100 km/h (62.14 mph) in just 7.5 seconds and never looks back until it reaches 226 km/h (140.43 mph). The TT Roadster accelerates to 100 km/h (62.14 mph) in 7.7 seconds and keeps going up to 223 km/h (138.57 mph).
These models—the world’s first diesel sports cars—consume an average of only 5.3 liters and 5.5 liters of fuel per 100 km (44.38 mpg and 42.77 mpg) respectively, which corresponds to CO2 emissions of a mere 140 g/km and 145 g/km. In so doing, they are setting a benchmark that represents a veritable quantum leap in the sports car segment. With the TDI engine in the TT series, Audi once again establishes its leading role on the diesel market. The brand with the four rings is advancing progress and starting at the top.
In keeping with the theme of sporty performance, Audi has combined its two diesel-engine sports cars with highly effective manual six-speed transmissions whose short lever travel allows the driver to shift quickly, easily and precisely. The housings for these transmissions are made of lightweight, high-tech magnesium materials. Relatively long final transmission ratios have been employed to bring the drivetrain in line with the character of the TDI engine.
In light of their high torque values, Audi is equipping both of its new TT models with quattro permanent all-wheel drive. The heart of this system is an electronically controlled, hydraulically activated multi-plate clutch, which is located in the rear of the vehicle for improved weight distribution. This clutch generally distributes up to 85 percent of the engine power to the front axle and 15 percent to the rear axle; in extreme situations it can divert up to 100 percent of the power to either axle.
The overall concept: An exercise in uncompromised sportiness
Consistent efforts to reduce vehicle weight are also part of the efficiency strategy pursued by the brand with the four rings. Both sports cars are very lightweight: the 2 + 2-seater TT Coupe weighs only about 1,370 kilograms (3020.33 lbs) when empty, while the two-seater TT Roadster with soft top weighs roughly 1,415 kilograms (3119.54 lbs). Underlying these low weights is an innovative hybrid body construction developed by Audi. Front components are made of aluminum and utilize Space Frame technology; rear components are made of steel. This solution guarantees that the frame is as rigid as possible and optimizes load distribution between the axles.
The Audi TT Coupe and TT Roadster are dynamic, emotion-packed sports cars. As was the case with preceding models, these cars are impressive for their powerful design, whose dynamic flow continues on into the interior. The cockpit contains multiple nods to the circle motif, and the sports steering wheel with its flat-bottomed rim fits the driver’s hand like a glove. The sport seats are deep-set, providing a sporty seated position and firm lateral support. The backs of both rear seats fold down in the TT Coupe, making the trunk space grow from 290 to 700 cubic liters (10.24 – 24.72 cubic ft). The Roadster (250 liters, 8.83 cubic ft) comes with a practical load-through hatch upon request.
The sports suspension likewise offers extraordinarily dynamic features. The front suspension is pivoted on an aluminum subframe and has a wide track measuring 1,572 millimeters (61.89 inches).
A highly precise rack-and-pinion steering system with a direct steering ratio provides an intimate link between the driver and the road. Power steering with servo assist, which decreases as speed increases, is generated by an electromechanical drive that is even more efficient than a hydraulic pump.
The coil springs and shock absorbers in the four-link rear axle are situated in separate areas. The links are also finely differentiated: The layout of the trailing links, which absorb the propulsive and braking forces, is relatively soft to promote a comfortable ride. The connections to the three transverse links per wheel, on the other hand, are rigid in order to direct transverse forces into the body with precision.
The Audi TT Coupe 2.0 TDI quattro and Audi TT Roadster 2.0 TDI quattro roll on 16-inch, cast aluminum wheels fitted with 255/55 R16 tires. Behind the wheels are large disk brakes with pads that develop large coefficients of friction. The ESP stabilization program supports the neutral to slight understeering feel of the TT—the finishing touch on an overall portrait of exciting dynamics, exhilarating driving pleasure and stability you can count on.
Audi magnetic ride, a high-tech shock-absorber system available as an option, is an adaptive system that resolves the traditional conflict of interests between comfort and handling. A magneto-rheological fluid circulating in the shock absorbers changes the direction of the magnetic particles within milliseconds when electricity is applied; this alters the overall characteristics of the fluid and, in turn, modifies the damping characteristic. The driver can choose between “Normal” and “Sport” programs by flipping a switch.
Equipment makes a statement of refined style
Standard equipment for both of the new TT models reflects the sporty character and refined style of the series. Faux aluminum accents add a shine to gray inlays and various other components in the interior. The sports steering wheel comes with a Nappa leather cover. The climate control system (standard for the TT Coupe) regulates heating and ventilation in response to the level of sunlight. The driver information system and chorus audio system round out the standard equipment.
A wide array of high-tech equipment is available as options, including a highly modern generation of audio devices, electrically adjustable front seats, the adaptive light dynamic cornering light system and two navigation systems with a user interface based on the Audi MMI concept—a cut above the competition.
[Source: Audi via CarScoop]
