We love German tuning companies. Just when you think they've gone too far, they come with something more extreme, and you don't get much more extreme than a 275bhp Fiat 500 Abarth.

You have tuning firm Hamann to thank for this slice of insanity, taking the 500 Abarth's turbocharged 1.4-litre engine to more than twice its standard power output and upping torque to 280lb.ft. There are no performance figures for this conversion available as yet, but fortunately Hamann also includes uprated brakes and suspension, and a limited slip differential, as part of the deal.

There's also a revised gearbox that introduces a new top gear ratio to reduce engine revs by 500rpm when the car is flat out. Hamann says this safeguards the engine, which has a race-spec cylinder head, pistons, camshafts and turbocharger. A new exhaust and race clutch are also fitted.

If this is all a bit too nutty for you, Hamann offers less potent engine upgrades for the 500 Abarth. These start at 160bhp, rising through 180- and 210- to 240bhp. All come with improved braking and Hamann also offers its own 18-inch alloy wheels.

Less enticing than the performance upgrades is Hamann's attempts at restyling the Fiat 500 Abarth. If you want to go the whole hog, you can order side skirts, beefier wheelarches and a front spoiler that juts out. To round things off, the rear bumper can be ordered with diffuser and no less than four exhaust pipes.

On the inside, it's a little more restrained with only new aluminium pedals and floor mats with the Hamann logo stitched into them. We'll check it out in Geneva.

Alisdair Suttie - 26 Feb 2010