The most extreme version yet of the McLaren MP4-12C has been revealed. The McLaren 12C Cam-Am edition racing concept will make its debut at the Pebble Beach Concours this weekend.

The one-off track-focused concept is based on the McLaren MP4-12C GT3 race car but, free from race regulations, the 3.8-litre twin-turbo V8 has been revised to develop 630bhp. Key changes are to the engine calibration and cooling system. Dry weight is 1200kg.

McLaren claims downforce has been increased by 30 per cent over the standard car. The 12C Cam-Am’s aero package includes a carbonfibre front splitter, rear diffuser, dive plane winglets and a rear wing supported by polished aluminium mounts. Extensive use of carbonfibre for the wing mirrors, engine cover and side cooling vanes contrast with the McLaren Orange paint — a tribute to the cars of Bruce McLaren and Denny Hulme.

Exterior revisions are completed by black satin forged lightweight alloy wheels and Akebono brakes.

The cabin features race seats, six-point harnesses and a race-spec roll cage. The steering wheel has been carried over from the GT3, with a shape and grip derived from Lewis Hamilton's F1 car.

Watch Autocar's video review of the new McLaren MP4-12C