The tradition of the sporty top Polo model versions reaches back nearly a quarter of a century and is based on the legendary Polo Coupé G40 from 1986. As the first car ever to be equipped with a mechanical G-charger – it re-defined the vehicle dynamic limits in this segment. Its engine had a power of 83 kW / 113 PS and made the Polo G40, which in top condition today is a coveted collector's item, nearly 200 km/h fast. In contrast, the predecessor of the new Polo GTI first switched over to turbo technology in the year 2006. Its base version had a power of 110 kW / 150 PS; the legendary Cup Edition then took this figure up to 180 PS.
Back to the future: At the end of May, the first new Polo GTIs will appear in Germany, and will then progressively be introduced across Europe and in Japan. The combination of direct injection, supercharger and turbocharger under one engine bonnet will generate plenty of excitement in this segment. The 180 PS Euro-5 16-valve four-cylinder engine reaches its maximum power at 6,200 rpm. Its maximum torque of 250 Newton-metres is also impressive for an engine of this size. It is already there from 2,000 rpm and stays at a constantly high level up to 4,500 rpm. These numbers highlight the fact that very torque-strong and rpm-loving 1.4 TSI has an easy game of it with the Polo GTI. It breathes a rare level of agility into the quick front-wheel drive car in all of life's situations and at all engine speeds.
Weighing 1,194 kg, the Polo GTI accelerates to 100 km/h in just 6.9 seconds and reaches a top speed of 229 km/h. At the same time, it is the most fuel efficient and lowest emitting GTI ever produced. Combined fuel consumption: just 5.9 litres per 100 kilometres. That is equivalent to CO2 emissions of just 139 g/km. By comparison: Its direct predecessor with regard to power – also equipped with a 180 PS 1.8-litre turbo engine - consumed 7.9 litres per 100 kilometres (equivalent to 188 g/km CO2). This means that the new car is 25 percent more fuel efficient. That's real progress.
Technology of the 180 PS TSI in detail
Especially interesting from a technical perspective is a look at the complementary operating modes of the supercharger and turbocharger. The mechanically belt-driven supercharger boosts the TSI's torque at low engine speeds. Its engine charging is based on the Roots Principle. A special aspect of the supercharger used here is its internal gearing, which enables a high compressor power boost at low engine speeds.
At higher engine speeds, the turbocharger is also activated (with wastegate control). The supercharger and turbocharger are arranged in series here. The supercharger is actuated by a solenoid integrated in a module within the water pump. A control door ensures that the proper amount of fresh air reaches the turbocharger or supercharger for any given operating point. In pure turbocharger mode, the control door is open. The air then follows the familiar and conventional path for turbo engines: via the front intercooler and throttle valve to the inlet pipe. Starting at an engine speed of 3,500 rpm, the supercharger turns all of the work over to the turbocharger.
DSG transmission: Extremely efficient, extremely sporty
Having a positive effect on this dynamic is the standard 7-speed DSG. The direct shift gearbox unifies the sports appeal and economy of a manual gearbox with the operating convenience of an automatic. As an alternative to the fully-automatic mode, the DSG may also be shifted manually – either by gearshift lever via the Tiptronic shift gate or via the standard shift paddle on the steering wheel.
The world's first 7-speed DSG for large-scale production has – as its most prominent design characteristics – two dry clutches whose pressure is regulated hydraulically. Engine power is transmitted to the dual clutch via the crankshaft and a dual-mass flywheel. Clutch I handles the odd-numbered gears, and clutch II the even gears plus reverse gear. The results of this sophisticated clutch management: when shifting, there are no gaps in propulsive power. Comfort and convenience are excellent, and the driver experiences an incomparably dynamic yet comfortable shifting feeling.
Responsible for this – along with an intelligent mechatronic system (electro-hydraulic transmission control) – are two clutches as well as two drive shafts and three final drive shafts. This networked system makes it possible to continually "lie in wait", ready to go into action at the next higher driving level. And indeed it is lightning-fast. Example: while the Polo is driven in sixth gear, the seventh gear is already engaged, but is not yet "active". As soon as the ideal shifting point has been reached, the clutch responsible for sixth gear automatically opens, while the other one closes and "pre-activates" seventh gear. This produces an overlap between opening and closing of the two clutches, and this leads to the comfortable shifting described above. The entire shifting process is completed within a few hundredths of a second, which is much faster than even the most highly trained professional driver could achieve.
Some exciting numbers about the 7-speed DSG
- 1.7 litres oil flow in the 7-speed DSG
- 70 kilograms: weight of the 7-speed DSG
- 250 Newton-metres: maximum torque of engines that can be paired with the 7-speed DSG
- 2003: year in which the first DSG was introduced
(in the Golf R32)
- 2005: launch year of the 1001 PS Bugatti Veyron 16.4 with DSG
- 2007: series production of the 7-speed DSG began at the end of this year (first used in the Golf TSI with 90 kW)
- 2009: 7-speed DSG was first used in the Polo in this year
Notes:
TDI, TSI, DSG and Twincharger are registered trademarks of Volkswagen AG or other companies of the Volkswagen Group in Germany and other countries.
Equipment information and technical data apply to models offered in Germany. They may differ in other countries.