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More efficient engine-transmission pairings in the updated Audi Q5 reduce fuel consumption up to 15%; hybrid quattro
27 April 2012
|Audi Q5. Click to enlarge.|
Audi is launching its completely updated Q5 SUV series with five engine options: three TDI (diesel) and two TFSI (gasoline) engines, as well as the Q5 Hybrid Quattro (earlier post, earlier post for more details on the hybrid technology). All of these engines combine direct fuel injection with charging, and a start-stop system is standard in all versions. Although most of the engines have enhanced performance, their fuel consumption values were reduced by up to 15%.
Diesels. The most efficient Q5 series engine is the 2.0 TDI; Audi offers it in two versions. In the version with 105 kW (143 hp) and 320 N·m (236 lb-ft) of torque, the four-cylinder engine in combination with manual transmission and front-wheel drive has an average fuel consumption of 5.3 liters of diesel per 100 km (44 mpg US), and a CO2 equivalent of 139 grams per km (224 g/mile). The 75 liter (20 gallons US) fuel tank enables driving ranges of up to 1,400 km (870 miles).
The Audi Q5 with 130 kW (177 hp) and 380 N·m (280 lb-ft) of torque (with S tronic and quattro drive) has a fuel consumption value of 6.0 liters per 100 km (39 mpg US). The 3.0 TDI delivers 180 kW (245 hp) and 580 N·m (428 lb-ft) of torque. The V6 diesel—which appears in a new, advanced design and is always paired with a seven-speed S tronic and quattro drive system—accelerates the Q5 from zero to 100 km/h (62 mph) in 6.5 seconds and has a top speed of 225 km/h (140 mph). Its combined fuel consumption is 6.4 liters of fuel per 100 km (36.8 mpg US).
Audi Q5 Hybrid Quattro. The Q5 Hybrid Quattro, the first hybrid model from Audi, is designed as a parallel hybrid. Propulsive power is supplied by a 2.0 TFSI with 155 kW (211 hp) and 350 N·m (258 lb-ft) of torque as well as an electric motor with a peak output of 40 kW (54 hp) and peak torque of 210 Nm (155 lb-ft). Together, the two power sources can briefly output a system power of 180 kW (245 hp) and a system torque of 480 N·m (354 lb-ft).
The Audi Q5 hybrid quattro accelerates from zero to 100 km/h (62 mph) in 7.1 seconds and can reach a top speed of 225 km/h (140 mph). In pure electric mode, it can cover up to three kilometers (1.86 miles) at a constant speed of 60 km/h (37 mph). In this mode, its top speed is 100 km/h (62 mph), while its combined fuel consumption is 6.9 liters per 100 km (34 mpg US).
A highly modified eight-speed tiptronic transmission transfers engine power to the drivetrain without requiring a torque converter; its mounting space is taken by the electric motor, which is combined with a multi-plate clutch. The clutch engages and disengages the electric motor and the TFSI. A compact and lightweight lithium-ion battery system with 1.3 kWh energy capacity stores electrical energy. An air-cooling system maintains battery temperatures within a suitable window.
The driver switches between the three driving modes with a button and with the tiptronic gear selection lever. The EV characteristic map prioritizes the electric drive, while the D mode efficiently controls both the internal combustion engine and electric motor. The S mode and the manual shift gate of the tiptronic are configured for a sporty style of driving.
Within these constraints, the hybrid control module chooses the best operating mode at any given time. The Audi Q5 hybrid quattro can be driven with just the TFSI, just the electric drive or in hybrid mode. It can also recover energy during deceleration, or it can boost output for powerful acceleration when both drives work together.
Special instruments display the hybrid’s operating state, such as the powermeter, which replaces the tachometer.
Gasoline. A highlight of the TFSI engine line-up is the new two-liter, four-cylinder engine that has numerous innovations such as in the control of valves and their stroke, innovative thermal management, the fuel injection system, turbocharger and integration of the exhaust manifold in the cylinder head.
The new 2.0 TFSI outputs 165 kW (225 hp) and 350 nm (258 lb-ft). Its fuel consumption (with a manual transmission) is 7.6 liters per 100 km (31 mpg US). Producing even more power is the new 3.0 TFSI—the three-liter V6 with supercharging, which replaces the 3.2-liter engine. This engine outputs 200 kW (272 hp) of power and 400 N·m (295 lb-ft) of torque. Key performance data: zero to 100 km/h (62 mph) in 5.9 seconds, top speed 234 km/h (145 mph), combined fuel consumption of 8.5 liters per 100 km (27.7 mpg US).
Transmissions. Each of the engines in the updated Q5 has an optimal transmission system. The four-cylinder engine operates with a manual six-speed transmission as standard equipment. The eight-speed tiptronic is available as an option for the 2.0 TFSI with 165 kW (225 hp); it is standard in the 3.0 TFSI. The sporty seven-speed S tronic, on the other hand, is standard in the 3.0 TDI and available as an option in the 2.0 TDI with 130 kW (177 hp).
The transmissions are integrated in the innovative thermal management system of the four-cylinder versions, a system that significantly shortens the warm-up phase after a cold start.
All transmissions have wide gear spreads—the long gear ratios in the upper gears reduce fuel consumption, while the short gear ratios of the lower gears improve dynamic performance in highway driving.
The quattro permanent all-wheel drive system is standard with all but one engine—only the 2.0 TDI with 105 kW (143 hp) has front-wheel drive. Normally, the center differential distributes engine power to the rear and front axle at a ratio of 60:40, but it can redistribute the power quickly when necessary. The torque vectoring system finishes its job with finely tuned brake interventions.
Chassis. The chassis of the Audi Q5—with its five-link front suspension and trapezoidal-link rear suspension—adds new refinement and comfort in the characteristics of the springs, shock absorbers and stabilizers. The new electromechanical power steering system gives the driver a better feel for the road with direct gearing. The system—which adjusts its power assist to vehicle speed—does not consume any energy in straight-line driving, reducing fuel consumption by about 0.2 liters per 100 km.
The electromechanical parking brake may be supplemented with the optional Audi hold assist, and the standard downhill assist function controls vehicle speed on steep descents. Electronic stabilization control (ESC) adapts its interventions to characteristics of the road surface.
The Audi drive select system lets the driver vary the characteristic of the accelerator pedal, the shift points of the automatic transmission, amount of power steering assist and operation of the automatic air conditioning system via four modes, including an efficiency mode. When an Audi navigation system is ordered, a fifth mode is added that is largely user-programmable.
In addition, three optional components may be integrated in Audi drive select. They are adaptive cruise control, chassis with damping control and dynamic steering, in which the steering gear ratio is modified as a function of vehicle speed via a harmonic drive system. At performance limits in driving through curves, it compensates for understeer and oversteer by intervening with slight steering pulses.
Driver assistance systems. Assuming a central role among the optional assistance systems is adaptive cruise control. The radar-based cruise control system controls the distance to the car ahead in traffic; at speeds below 30 km/h (18.6 mph) it can initiate hard braking if it detects an impending collision. Audi active lane assist can support the driver with small steering interventions to stay on track in a lane. Audi side assist monitors the space behind the Q5 to support the driver in changing lanes.
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