New more powerful Golf R is up to 18% more fuel efficient
20 August 2013
|New Volkswagen Golf R. Click to enlarge.|
Volkswagen has introduced the new Golf R, the flagship of the model series. Powered by a newly designed 296-horsepower (221 kW) TSI engine which is 30 hp stronger than the engine in the previous model, the new Golf R is up to 18% more fuel efficient than its predecessor when equipped with the optional DSG transmission.
With a manual transmission, the Golf R accelerates to 62 mph in 5.3 seconds, an improvement of 0.4 sec over the previous Golf R. With the DSG dual-clutch automatic transmission, the time is 4.9 seconds. The Golf R’s top speed is electronically limited to 155 mph (249 km/h). Fuel consumption of the Golf R was reduced from 8.5 l/100 km (28 mpgUS) in the previous model to 7.1 l/100 km (33 mpgUS).
CO2 emissions also improved from 199 to 165 g/km. Equipped with a Stop-Start system, battery regeneration, and the optional DSG transmission, the car is even more fuel efficient, with an EC Combined figure of 6.9 l/100 km (34 mpgUS) and 159 g/km CO2. Fuel savings compared to the previous model with DSG (8.4 l/100 km) are 1.5 l/100 km, which represents the mentioned 18% improvement.
The new Golf R has a more advanced version of the EA888 four-cylinder turbocharged and direct-injection 2.0-liter engine that’s fitted to the new Golf GTI. Compared to the 227 hp (169 kW) GTI engine, the engineers boosted power by 69 hp to 296 hp, delivered at 5500 rpm, thus creating one of the most powerful four-cylinder production engines in the world.
Maximum torque has been increased by 22 pound-feet to 280 lb-ft (380 N·m), available over a broad speed band from 1800 to 5500 rpm. To attain this output, the Golf R’s 1984-cc engine was subjected to a motorsports-style development program. The following components were modified or completely redesigned compared to the GTI engine: the cylinder head (together with exhaust valves, valve seats, and springs); pistons; high-pressure injection valves; and turbocharger.
Many of the EA888 series engines have innovative engineering solutions such as water-cooled exhaust gas channels running through the cylinder head to the turbocharger (to reduce efficiently full-load fuel consumption) and a dual injection system with direct injection and multi-port injection.
With its new fully-electronic coolant control system, the Golf R’s TSI engine has much more efficient thermal management with a reduced warm-up phase; this reduces frictional losses and fuel consumption. In addition, the TSI engine has variable valve timing on both the intake and exhaust sides, as well as two-stage exhaust-valve lift. This enables optimal control of the charge exchange process for better performance, fuel economy and low emissions.
The Golf R has always used 4MOTION permanent all-wheel drive. The latest generation system is now being used in the fourth-generation Golf R. Using refinements such as the Haldex 5 coupling, the 4MOTION system is activated before any wheelspin occurs, eliminating nearly all traction losses. The system achieves this by using an advanced control function based on specific driving conditions. When operating under a relatively low load or when coasting, the front wheels are driven and the rear axle is decoupled, helping to save fuel. However, the rear wheels can be variably engaged in fractions of a second whenever necessary. This is done via the Haldex coupling, which is activated by an electro-hydraulic oil pump.
A control unit continually calculates the ideal drive torque for the rear wheels and controls how much the multi-plate clutch should be closed by activating the oil pump. The oil pressure increases the contact pressure at the clutch plates in proportion to the torque desired at the rear axle. So, the amount of pressure applied to the clutch plates can be used to continuously vary the amount of torque going between the front and rear wheels. If necessary, nearly 100% of the drive torque can be directed to the rear wheels.
In addition to the Haldex coupling that acts as a longitudinal lock, four electronic differential locks (EDS) that are a function of the electronic stability control system act as lateral locks. The system briefly brakes a wheel that is slipping, enabling uninterrupted and stable transfer of drive power to the wheel on the opposite side.
In addition, the Golf R is equipped with the cross differential lock (XDS) at the front and rear axles. In the latest version, known as XDS+, this functionality is applied to a larger range of dynamic performance, making the vehicle more agile. When the car is being driven fast, brake pressure is applied to the inside wheel to restore optimal traction as soon as the electronics detect excessively light loads. XDS+ thereby operates as a transverse differential lock that compensates for understeer during fast cornering.
The new Golf R is equipped with “ESC Sport” as standard. The system is activated by a two-stage switch on the center console. When the driver presses this switch briefly, Electronic Stability Control (ESC) switches to the “ESC Sport” mode. In very fast driving with lots of bends, such as on a race track, the ESC system has a higher threshold. When the ESC button is pressed for longer than three seconds, the system is fully deactivated for high-performance driving on a track, a feature that is available only on the Golf R.
The Golf R features a sport suspension setup that is specifically tuned to the car. Compared to the base Golf, its ride height was lowered by 0.8 inches, which makes the Golf R lower by 0.2 inches than the GTI.
Like the Golf GTI, the Golf R is equipped with the newly developed progressive steering system as standard. With progressive steering, there are 2.1 turns of the wheel (380 degrees) from lock to lock, compared with 2.75 turns (500 deg) for less powerful Golf models it takes 2.75 turns. The new steering operates with a progressive gear ratio, perceptibly reducing steering effort in maneuvering and parking. On country roads with lots of bends, the experience is enhanced because the steering is more direct.
The new Golf R can be ordered with the second-generation DCC dynamic chassis control as an option. DCC offers three driving modes: Comfort, Normal, and Sport. In Sport mode, the dampers are stiffened for more agile handling.
The DCC system adaptively controls the damper valves via a further developed and refined control algorithm. DCC takes input signals from wheel displacement sensors and accelerometers as well as vehicle information from the Chassis-CAN bus to compute these values and adaptively adjust the optimal damping force for every driving situation. Moreover, damping forces are selectively applied to the four wheels individually. With the new generation of DCC, it is now possible to independently vary rebound and compression damping while cornering.
The Driving Profile Selector has four programs in the Golf R, and five in conjunction with DCC: "Eco”, “Normal”, “Individual”, and a “Race” mode that has been specially designed for the Golf R. In combination with DCC, “Comfort” mode is also available. All modes were specifically tuned for the Golf R.
In “Race” mode, damping is increased and engine response and the shift points of the DSG transmission are configured to be even sportier. In the “Individual” driving profile, the driver can combine mode settings for various individual parameters. In the “Eco” driving profile, on the other hand, the engine controller, air conditioning, and other auxiliary units are controlled for optimal fuel economy. Vehicles with DSG also have a coasting function in Eco mode: When the driver releases the accelerator pedal, such as slowing down for a traffic light or going downhill, the DSG disengages and the engine idles.
The market launch of the Golf R as a two and four-door car will take place in the fourth quarter of this year.
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