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Doesn't look like much, does it? A pretty standard Volkswagen Golf, regulation silver, riding on a modestly sized set of 16-inch alloy wheels. But, according to its maker, this car represents the future of petrol engine technology.
Under the bonnet of this Golf is a new-generation powerplant called TSI. It's a complex system, but if you're technologically challenged like me, this is all you really need to know - the T stands for "twincharging" and indicates the engine is fitted with both a supercharger and turbocharger.
The motor is small in capacity at 1.4 litres, but makes a lot of power. At 103kW it's just 7kW down on the Golf 2.0-litre FSI that it replaces, but it makes 20Nm more torque - an astonishing 220Nm served up at 1500rpm.
Using a small-capacity motor means less friction and greater potential for economy and clean-running, but adding technology such as direct injection, which is used on all VW petrol motors, and twincharging produces enough grunt to compete with cars a whole class up.
Supercharging and turbocharging are both methods of forcing extra air into the engine, which improves efficiency and therefore the output.
A supercharger is driven directly by the engine and produces instant response, but works better at low revs and has the downside of creating extra drag on the powerplant. A turbocharger is driven by waste exhaust gases and is great at generating power at higher speeds since it can spin very quickly, but can also take some time to spool up - hence the term "turbo lag".
The TSI engine uses a supercharger from idle to about 3500rpm, then disconnects from the blower and switches over to the turbo for the high-end stuff. It's a brilliantly simple idea, but it's not one that's been tried on a mainstream car before.
If it does sound a bit familiar, that's because we saw TSI in New Zealand at the end of last year in the Golf GT. That limited-run car used a higher-output 125kW/240Nm version of the same 1.4-litre engine and was pitched as a high-tech hot-hatch alternative to the existing Golf GTi 2.0-litre.
But the case for the new, more mainstream Golf TSI is much stronger. The diesel-like low-speed response, fantastic rolling acceleration and intriguing soundtrack make it a no-brainer over the old 2.0-litre FSI model.
At $42,990, the TSI is $500 more expensive than the car it replaces, but has gained the twin-clutch DSG transmission and stability control. So it may have less engine capacity, but you're getting more performance and more equipment for your money.
The only let-down is the low-rolling resistance rubbers fitted to the TSI, which induces slightly soggy handling. On a decent set of rubber, this would be a very entertaining car.
Economy? With a combined figure of 7.1 litres per 100km, the Golf TSI is even-stevens with the old 2.0-litre FSI. But you wouldn't say the technology is standing still.
The TSI's driving characteristics and real-world performance are vastly superior to the old car, and the small-capacity engine gives the potential for much greater gains in gentle around-town running.
The TSI technology in this Golf is not to be confused with the "TFSI" powerplant used in the GTi model and Eos convertible, which is simply a turbocharged version of the standard 2.0-litre engine. No, carmakers don't make it that easy with all their odd acronyms. But the Golf TSI is an easy car to live with and a lot of fun to drive. It's a genuine step forward.
Small engines with big power outputs - VW is leading the way, but others will follow. Later this year we'll see a 1.4-litre turbocharged version of the Fiat Ritmo that makes an astonishing 110kW. It's a hard concept to get your head around, but one that we capacity-obsessed Kiwis might have to get used to.
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