Motoring: Torque of the town

Let's get straight to the point. Torque. If this sounds too technical already, please bear with me. Power is the glamorous measure of an engine's ability to make a car go, but torque is the revealing one. Torque is the measure of an engine's shaft-twisting ability, a measure of musclepower if you like.

There's a version of the new Volkswagen Polo which has more of this than you would expect. And the results are surprising.

The new-look Polo range, on sale in the UK from January, contains several interesting versions including a smart and racy-looking GTI with a 125bhp engine. And, curiously, there are four Polo 1.4s.

These are a leisurely 60bhp eight-valver, two 16-valve versions with 75 and 100bhp respectively, and the one with the engine of whose torque I have been talking. It's a very special turbodiesel, a serious pointer to global-warming reduction and the powering of future high-performance cars.

At this point it's necessary to interject that the Government's stance, unique in Europe, of making diesel fuel as expensive as petrol is way off the environmental message. The best modern diesels are super-clean, super-economical and super-efficient, and this model falls fairly and squarely into that class.

This engine, tiny by diesel standards, delivers 144lb ft of torque. That's nearly as much as a Ford Galaxy 2.3, for example, can manage.

It achieves this with the help of "unit injectors" which squirt fuel, in micro-controlled amounts, at the scarcely believable pressure of 29,000lb per square inch. So it atomises rather well, which means nearly all of it goes towards making the engine go and very little comes out as soot and nastiness.

As if to underline the message that this is a special and unusual engine, it has just three cylinders. So it makes an unusual noise, a smooth, low- pitched hum reminiscent of a six-cylinder engine running at half the speed. It gives the model a personality far stronger than any Polo has exuded to date.

Before I describe the driving experience, though, some more about the Polo's re-make. It looks like a facelift, but it's more than that. The Polo, as launched five years ago, is a car with which itself and its owners are comfortable: classy yet classless, fashionable yet ageless, all the things that a Volkswagen should be. But don't think it has been beyond improvement, because Volkswagen's senior supermini most assuredly has not.

So the new car has an interior as airy and inviting as the old one was dark, slabby and oppressive, plus revised suspension and a stiffer structure to banish the bounces, wobbles and rattles. At first glance it looks as though just the nose and tail have changed, with a bigger front grille and a rear number plate set, Golf-like, in the bumper, but actually every outer panel is new (galvanised, too) and the gaps between them are smaller.

The new cabin resembles that of the Polo's junior, the Lupo, with knobbly textures, almost none of the leathergrain that dominated before, and a dashboard which slopes down towards the front-seat occupants. The dials sit in a single cowling on top of the dashboard, unlike the Lupo's pair of separate cowls, and there's an air of quality all around which the old Polo, despite its brand values, did not have.

The suspension changes, which include front wheels set 20mm further apart, make a big difference. Today's Polo has a precision and speed of steering response almost unrecognisable to a driver of the old car, and there's less heaving and bouncing in bends and over bumps (although too much remains). All the better, then, to enjoy the star of the range, that 1.4 TDI.

I broke out into a smile as soon as I drove off, because there's so much thrust available for so little effort. Squeeze the accelerator, hear a distant turbocharger whistle and a deepening of that gruff note, and you'll be squirted past a slower car with a languid confidence that just doesn't compute with the fact you're in a Polo 1.4. You barely need to change down a gear; you just let that torque do the work.

Don't be misled by that wheel-spinning, tyre-smoking 0-60mph time, which is merely good. This engine is about accessible performance, lots of it, combined with the ability to travel around 64 miles on a single gallon of diesel oil. It's a brilliant solution.

Strangely, though, despite all this effort the revamped Polo range will be around for just two years. Then there'll be an all-new one, based on the VW group's new small-car substructure already seen under the just- launched Skoda Fabia.

That car rides and handles better again than this latest Polo, which bodes well for the next range. You can't, however, get the Fabia with this fantastic 1.4 TDI engine, because it's deemed too expensive for a Skoda. Better spend more and buy the Volkswagen, then.

Road Test

Specifications

Volkswagen Polo 1.4 TDI, from approximately pounds 11,000.

Engine: 1,422cc unit-injector direct-injection turbodiesel, three cylinders, six valves, 75bhp at 4,000rpm.

Transmission: five-speed gearbox, front-wheel drive.

Performance: 106mph, 0-60 in 12.6sec, 59-64mpg.

RIVALS

Fiat Punto JTD: from pounds 9,995. A big 1.9-litre, common-rail turbodiesel which can deliver strong, languid performance but, like other rivals here, can't quite match the Polo's economy. A stylish car, for all that, full of clever design details.

Peugeot 206 HDI: pounds 11,500 approx. With 90bhp from its common-rail 2.0- litre turbodiesel, this sporty-looking 206 gives a fine blend of pace and parsimony. It is to be available imminently.

Seat Ibiza 1.9 TDI: from pounds 11,250. The subject of a recent facelift as major as the Polo's, the Seat continues with the VW Group's older 90bhp turbodiesel engine. Good-looking, fun to drive.

Vauxhall Corsa 1.5 TD CDX: from pounds 11,195. Older-tech engine in older- design car - an uncompetitive blend. You're better off looking elsewhere.