The new Aston Martin Rapide and Porsche Panamera Turbo have been pitted against each other in an exclusive Autocar test.

Both firms set out to build high-performance, front-engined sports cars that look like coupes but function as saloons, yet the two vehicles are so different in design and execution.

See the Aston Martin Rapide v Porsche Panamera pictures

Aston Martin Rapide first drive review

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The Panamera has forced induction for its 4.8-litre V8, plus a seven-speed dual-clutch transmission, four-wheel drive and a state-of-the-art information interface.

The Aston Martin appeals on a more traditional level, with a conventional 6.0-litre V12 breathing at atmospheric pressure and transferring its energy to the rear wheels alone through a normal, six-speed automatic gearbox.

The Aston is nothing less than gorgeous, but that's something only those employed in Zuffenhausen might rush to say about the Porsche.

Performance

In terms of performance figures, though, the Porsche is ahead. The 493bhp Porsche fights the 470bhp Aston, but the Panamera's 516lb ft of torque to the Rapide's 442lb ft is more significant - as is the fact it delivers it from 2250rpm, fewer than half the revs required by its rival.

But being outpowered doesn't mean being outmanoeuvred. The Rapide's chassis feels as if it has been honed until no further improvement was possible. It rides more firmly than the Porsche, but with no great harshness. What's more, the steering is bizarrely communicative given the car's weight. It is only 20kg lighter than the Panamera, but on a decent B-road it feels clsoer to half a tonne less.

On a mountain road in Wales, the Aston never got left behind by the Panamera, and the German car was strangely remote and joyless to drive by comparison.

Space

In terms of everyday use, the Porsche wins the space race with derisory ease. It's also far easier to operate, no illegible dials or unintelligible navigation. The interior is also Porsche's best - a place of genuine luxury and quality - and is refined in ways the Aston can only dream of.

The Porsche will also use less fuel, and has a far larger boot, and would work for a ski holiday, thanks to its four-wheel drive.

Interestingly, though, the Aston is the quieter car - this is the most refined Aston in history.

Which to buy?

The Aston costs almost half as much again as the Panamera, so should we expect more? No, because Porsche will sell 10 Panamera's for every Rapide. You pay for that exclusivity.

If you are looking for a business tool, then there's no comparison. You must take the Porsche.

But the Panamera's only major failing is also its comeuppance here; it fails to communicate on an emotional level.

The Aston is close to the Panamera technically - more so than you'd imagine. But whether you look at it, listen to it or get in and drive it, it just grabs your heart.

If you could afford either, take the Rapide without a second thought.

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