Reviews

The rounded tail with inset light is also familiar, though now it comes with an interesting-looking grille below to disguise the mechanical bits and mount the single prominent exhaust.

The similarity is no accident: the S-IV has been styled by Steve Harper - now a Volvo designer - who made such a fine job of wrapping the three-wheeler's spaceframe and BMW bike mechanicals in a convincing body. The four-wheeler is wider and longer than the three-wheeler, but its lack of overhangs and stylish simplicity make it even more compact than the Lotus 340R.

Performance should be stunning. Grinnall has built the car around Fiat's powerful 2.0 litre five-cylinder turbo engine and has cut a deal with the Italian firm for direct supply on favourable terms. Power is a spectacular 220 bhp at 5750 rpm, accompanied by torque of 228 lb/ft at just 2500 rpm. Strap that - plus Fiat's six-speed gearbox to a package weighing less than 650kg and you have a recipe for truly massive performance.

Under the pretty composite body lies an extremely strong spaceframe chassis designed by Neil Williams. The front suspension uses unequal length wishbone and coil-over-damper suspension units.