Corvette ZR1 in Detroit Motor Show

General Motors has unveiled its fastest, most powerful production model ever. Official figures have yet to be released but insiders say the Corvette ZR1 is likely to top 200mph and crack 60mph in a little over 3 seconds. Its new supercharged, 6.2-litre LS9 V8 makes 620bhp and 595lb ft of torque, which GM claims gives the ZR1 a better power-to-weight ratio than the Ferrari 599, Porsche 911 GT2 and Lamborghini Murcielago LP640.

And its specification goes some way to matching its super-exotic and far more expensive European rivals; the bonnet, roof and wings are all made of carbonfibre, and the ZR1 gets carbon-ceramic discs as standard.

The ZR1 will be the first Corvette to break the six-figure price barrier, costing around $100,000 when it goes on sale in the Unites States. GM won’t confirm officially that it will be sold in Europe, but privately insiders admit that it plans to, in left-hand drive only.

The 505bhp, 198mph Corvette Z06 sells for £64,000 in the UK but the weakening dollar could see the ZR1 on sale officially for around £75,000. Import one yourself – if you can find one - and you’ll make a massive saving.

GM has wisely avoided attempting to make any environmental claims for the ZR1: of all the General’s major Detroit debuts, this is the only one not to have a green angle. Buyers will be more interested in the polycarbonate window in the bonnet that gives a view of the new engine’s cam covers, or the new Magnetic Selcctive Ride Control that allows softer spring rates than the standard car for better ride, but instantly adjusts the damping when a firmer response is required. A close-ratio six-speed manual is the only transmission.