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VW Golf R Gains Horsepower and MPG at the Same Time

Sections: Fuel Economy, Powertrain

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Golf R VW Press Photo 2014

The Volkswagen Golf R has more power under the hood, but can also get better fuel economy than the outgoing Golf R, Volkswagen says.

The Volkswagen Golf R is gaining both power and fuel economy at the same time, if you believe the press release from the automaker.

The release said the VW Golf R has 296 horsepower — and increase of 30 horsepower over the outgoing Golf R — yet has 18% better fuel economy at 33 MPG for the manual transmission-equipped Golf R and 34 MPG for the Golf R with the optional DSG automatic.

Let’s think about 296 horses being pumped out of a production four-cylinder engine for just a moment. Consider it displaces only 2.0 liters, and the impressiveness of the performance equation increases. I’ve had a lot of V6 engines in test cars lately, and some of those barely edged the Golf R’s new horsepower rating despite having nearly twice the displacement. VW called it “one of the most powerful four-cylinder production engines in the world” and said it backs up all those horses with 280 ft-lbs of torque. We’ll let Volkswagen handle the techy details of the engine and other parts of the car:

Maximum torque has been increased by 22 pound-feet to 280 lb-ft, 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.

Efficient thermal management. 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. Thanks to 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.

4MOTION all-wheel drive system

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 per cent 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.

ESC Sport. 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.

Sport suspension
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. In the Golf R, the strut-type front suspension has a newly developed lower wishbone and the multi-link rear suspension was enhanced with new tuning of the toe link bearings.

The engineers designed the running gear of the new Golf R for maximum driving fun combined with extraordinary stability and good long-distance comfort. Compared to the previous model, steering response was improved thanks to the new “progressive” variable ratio steering rack. In addition, maximum attainable cornering speeds were significantly increased and understeer all but eliminated.

Progressive steering. 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.

DCC. 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’, which are selected and displayed via the center console touchscreen as part of the “Driving Profile Selector” functionality. 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.

Race mode. 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.

Brakes.
The Golf R has uprated brakes, shared with the GTI Performance. At the front, the car has 13.4-mm diameter vented discs that are 1.2 inches thick, while the rear rotors are 12.2 by 0.9 inches. The black brake calipers have the R logo on them: up front the brake pistons are 2.4 inches in diameter and are 1.7 inches at the back.

Exterior
Volkswagen R GmbH has developed numerous new exterior features for the flagship Golf. They include the bumpers, side skirts, rear diffuser, dual chrome exhaust tips per side, the lighting design, and standard 18-inch and optional 19-inch aluminum-alloy wheels.

Front end. The Golf R can be distinguished from the front by a new bumper design with exceptionally large air inlets, a modified radiator grille that sports an “R” logo, and newly developed daytime running lights that are integrated into the Bi-Xenon headlight housings. The LED daytime running lights form a distinctive dual “U” design beneath the headlights.

Side profile. From the side, the Golf R is characterized by newly designed 18-inch “Cadiz” aluminum-alloy wheels shod with 225/40 tires, black brake calipers with the “R” logo, body-color “R”-style side skirts, “R” badges on the front fenders, and “Matt chrome” door mirror caps. The car may also be ordered with optional “Cadiz” 19-inch aluminum-alloy wheels or “Pretoria” motorsports-style wheels.

Rear section. Rear details that define the new Golf R include smoked LED taillights with a distinctive light-colored stripe in the middle, an “R” design diffuser, four chrome tailpipes, and an “R” logo on the trunklid.

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