FOR SEVEN YEARS NOW, EACH APRIL and October, BMW engineers and their prototypes have been coming to north Wales, drawn by the roads, their unique and varied surfaces and the challenges they present for a chassis, and because the area is never too busy.
Today, evo is here as well. We’ve been invited to sample a pre-production version of the 523bhp, four-wheel-drive M850i, which is in the final throws of development ahead of its June launch. Beneath the camouflage wrap is a virtually off-tool car, with just a few prototype body and trim parts. Its chassis is evolved from that of the 7-series xDrive (not the new M5 with its two-wheel-drive mode) and it features adaptive dampers, rear-wheel steering, a new e-diff and, on this particular example, active anti-roll bars.…