QUICKEST CAT ON THE STREET; the JP1 is, by all definitions, a street-legal race car.(News)(Palmer Jaguar JP1)(Product/Service Evaluation)

Byline: MIKE DUFF

Shock and awe: The concept works. At least, it seems to in the overtaking lane of Britain's traffic-clogged A1(M) motorway, where what appears to be a Le Mans-bound prototype closes in at speed in the rearview mirror of dawdlers. The shellshocked drivers scatter.

Meet the Palmer Jaguar JP1, one of the most gloriously unlikely cars to have put on a set of license plates, certainly since Count Rossi's road-going Porsche 917 racer. And, in answer to the inevitable first question from stunned onlookers, yes, it is completely street-legal. Everything demanded by Britain's single-vehicle approval legislation is here-dipping headlights, turn indicators, speedometer, even a parking brake. But street-sensible?

In a word, no. With no doors, roof, windshield or heater, the JP1 offers no protection from the ravages of the merciless British winter. It's not cheap, either, costing about $87,000 at today's exchange rate (that's [pounds sterling]51,500). The equation does have a flip side, of course: the sort of performance that even the most exotic supercars can't come close to matching. Underneath the fiberglass bodywork there is a proper space-frame structure (bequeathed from an aborted project to produce a single-make racer), pushrod-operated springs and user-adjustable dampers. Power comes from a mid-mounted version of the 3.0-liter Jaguar AJ-V6, more commonly found powering the X-Type, heavily tuned and driving the rear wheels through the pure racer combo of a carbon composite clutch, Hewland FTR six-speed sequential transmission and limited-slip differential.

As you would expect from something that looks this ballsy, performance is towering. The official figures feel, if anything, pessimistic. What is not in doubt is that this is the quickest Jaguar-powered road car ever, with a claimed 3.6-second 0-to-60-mph time (0.3 second inside the XJ220's time) and a 0-to-100-mph time of just 6.8 seconds. That is superbike-quick. Top speed is limited by gearing to 180 mph.

Technically the JP1 isn't a race car, but only in that there's no race series for it. It was originally designed and engineered as a driver training car for Jonathan Palmer's race school at the Bedford Autodrome in England. (Dr. P's previous career highlights include driving in Formula One and being the man who set the McLaren F1's original 231-mph production-car speed record.) But our test car, the prototype, is far from a marketing gimmick. Production has already begun on the first batch of 10 road-goers, and six have already been sold on little more than word of mouth.

Despite its street legality the JP1's primary mission remains racetracks, and it promises ...