Austin MG Metro 6R4 Group B from 1986. Rally version

Austin MG Metro 6R4 Group B from 1986 with 410 HP in Monaco.

Created for the short-lived Group B rally category, the 4WD mid engined MG Metro 6R4 of 1984 (standing for 6-cylinder, Rally, 4-wheel-drive) was a world away from the best selling city car to which only bares superficial cosmetic resemblance to its ordinary counterpart.

The competition car effectively only shared the name of the production Metro as it featured a mid-mounted engine with four-wheel drive transmission enclosed within a semi-monocoque seam-welded tubular chassis. The development of this vehicle had been entrusted to Williams Grand Prix Engineering.

The resulting car was shown to the world in May 1985. It was powered by a David Wood designed bespoke 3-litre V6 powerplant which used some of the engine architecture of the Cosworth DFV. It featured twin overhead camshafts and four valves per cylinder.

The engine was not turbocharged as the majority of its competitors were, which considered the Metro as “unique.” The engine was mounted back to front in the car, with the forward end of the engine facing the hatchback and the gearbox attached conventionally behind it and, therefore, in the middle of the vehicle.

The four-wheel-drive was permanently engaged, and drove separate prop shafts to the front and rear differentials. The rear differential was mounted on the side of the engine sump with one driveshaft running through the sump to the nearside rear wheel. Much of the outer bodywork was made of GRP, with the only exception being the roof panels (which were aluminium), the steel doors, and the remaining panels from the original Metro shell. The doors were, however, concealed by plastic airboxes. Indeed, models now on show generally have stickers demonstrating where it is safe to push from when moving the vehicle, so as not to damage the bodywork.

The 6R4 appeared in two guises. There was a so-called Clubman model which was the road going version which developed in the region of 250 bhp (186 kW), of which around 200 were made and sold to the public for £40,000 (the homologation version). A further 20 were taken and built to International specifications which had a recorded output of over 410 bhp (306 kW; 416 PS)

At its launch in 1985, Rover announced that it would complete the necessary number of cars required for homologation by November of that year. This was undertaken at the group’s large manufacturing facility at Longbridge. The car was to participate in the Lombard RAC rally in November 1985, and an example, driven by works driver Tony Pond, finished a highly respectable third, behind two Lancia Delta S4s.

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