Aston Martin finally builds the Cygnet we deserve

It has a 4.7-litre V8 and is rear-wheel drive now. And there's only one. Sob.

It's not often that you read about the length of a torque tube in the opening paragraph of a car's press bumf - but in the case of the one-off V8 Cygnet, it's a standout feature. "It's no small achievement to fit the Vantage's 4.7-litre engine so harminously into the Cygnet's compact body," quipped David King, Aston's special operations officer. And yet it's the smallness of Gaydon's achievement that initially staggers. Just where has the V8 gone under that stupid snout of a bonnet?

A long way back, of course, is the answer. The Cygnet (which, you'll recall, was really a Toyota iQ) used to have rear seat(s) - after a fashion - which this one does not. It doesn't have the same bulkhead at the front either - surprise, surprise - nor the same transmission tunnel. No prizes either for figuring out that the front and rear track are a little different now, either. The subframes and suspension were derived from the last generation Vantage. The fuel tank is now in the boot.

The reason for all this freewheeling madness? Well, because a customer asked the 'Q by Aston Martin - Commision' service whether it was possible, and they presumably said, sure, for this amount of money, and the customer said yes. For Gaydon's part, it's the perfect advert for the personalisation department: you dream it up and we'll figure out how to build it. Sky's the limit. (Assuming the sky stops dead at the edge of the manufacturer's back catalogue.)

Still, the V8 Cygnet could conceivably have ended up as no less of a dog's dinner than the model on which it was based. But the interior says much about our hero. The roll cage was made an integral part of the chassis from the outset; there are composite, fixed back Recaro bucket seats with four-point harnesses; there is a FIA compliant fire extinguisher system; there is a removable Alcantara steering wheel. By gum, this Cygnet has been built to be driven. Hard.

That thought is a compelling one for good reason; installing 430hp into a three-metre long car has given it rather a lot of shove. According to its maker, it'll do 0-60mph in 4.2 seconds and go onto achieve what you'd imagine is a rather frenetic 170mph - fully 60mph faster than original ugly duckling. When you've have had enough of doing that, there are 380mm discs with six-piston monoblock calipers and 330mm discs on the rear to bring you back to reality. Fairly sure they weren't standard previously.

Truth be told, body panels apart, there's not really anything much of the Cygnet left. The dash is bespoke (the instrument cluster is from the Vantage); the seven-speed Sportshift II transmission is obviously carried over; the forged, five-spoke alloys are housed in carbon composite wheel arch extensions and the exhaust system - which is also rather short in length - is custom made. What you're left with then, via someone else's imagination, is a city car in Gaydon's own image. Which is probably why we love it.