Why does everyone want to turn the poor Audi A4 supersonic?

Audi already offers the slightly unhinged S iteration, boasting a 4.2-litre V8 that puts out 339bhp and propels the A4 to 60mph in just under six seconds.

And if you need to go even quicker, there's always the frankly deranged RS4, which develops a massive 414bhp from the same engine and hits 60 in under five seconds.

More? You want more? You'll have to go to Germany then. Audi tuning specialist Alfons Hohenester has rustled up this: the Hohenester HS650 Nardo.

OK, so the name makes it sound like an electro-pop synthesiser, but there's nothing cheesy about the performance.

This modified A4 is fitted with a three-litre twin-turbo V6, which will see it to 62mph in 3.4 seconds and on to a top speed of 214mph. It'll also develop 650bhp when it's spinning at 7,200rpm.

The A4 has race-tuned suspension and modified aerodynamics to keep it on the road at such silly speeds, but we like the fact that - if you took the gaudy stickers off at least - it looks more or less stock.

Rock up to the lights in it and you'd barely get a second glance. At least not until you hit a speed bump and landed in France...

Read Audi A4 car review

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Audi RS4 Cabriolet - July 31, 2006
Audi A4 Cabriolet - December 10, 2005
Audi A4 DTM Edition - September 8, 2005
Audi A4 RS4 - June 1, 2005
Audi A4 Cabriolet - March 8, 2002