The Porsche is a very different animal. And that’s down to torque – 479lb ft of it, all the way from 1900rpm to 5000rpm. The Audi, by comparison, needs 6500rpm to deliver just 391lb ft.
Porsche’s new 3.8 engine responds with almost no lag. This means that not only does this Turbo have more firepower than the last, but it’s also possible to meter it out more precisely. Net result? Much greater corner exit pace.
Once you become accustomed to just how accurate the 911’s throttle is, and how rarely you really need to call upon the Full Monty, oddly the Turbo feels less manic than the R8. This is partly because the revs are lower, but also because the engine feels further removed, like some magical nuclear reactor.
If that sounds uninvolving and unrewarding, it isn’t; it just needs a different mindset from the Audi, the sort that gains satisfaction from using a machine designed precisely for a purpose.
Which is quicker? Certainly the Porsche is easier to drive quickly on unfamiliar, narrow and unsighted roads, mostly because its torque advantage gains it so much time coming out of corners. No doubt if you drove the R8 with sufficient commitment it could match the Turbo, and on a smooth track it could well be quicker.
Which is the more rewarding to drive? Here in Wales, personally I prefer the Porsche, not because it has the better balance or the better engine, but because I find its controls instill more confidence. That’s a shame for the R8, because at its core it is the superior machine.
But the Porsche does not win this test, because while it might have a minor advantage in ground-covering ability, the Audi has it licked in the areas that matter most for open-top supercars. It is, night and day, the more desirable car – not my opinion, but that of everyone we asked on our travels. It also has the better hood – not the simplest or quickest, but the more theatrical and beautifully finished. Technically the open R8 stays truer to the coupé than the 911.
But the clincher is that the R8’s thrills are more accessible and more relevant, especially where these cars will probably be used most. The Turbo Cab impresses with crushing competence, but what it lacks is the one thing the R8 Spyder has in abundance: drama. And drama sells.
You can read the full test in this week's Autocar magazine, which is on sale now.
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