BMW took a famous win at the Le Mans 24 Hours in 1999 with the V12 LMR, but by the following year the company was already pumping its resources into its Formula 1 partnership with Williams.
Rather than throw leftover components away, however, BMW’s engineers decided to find out what would happen if they transplanted the racing car’s 6.0-litre V12 into an X5 to, as Autocar’s Andrew Frankel reported, “test the X5 concept to the limit”.
In its Le Mans race trim, the 6.0-litre motor pumped out 600bhp but only because it was forced by regulations to breathe through a restrictor in its inlet tract. For the special X5, Munich’s engineers removed the restrictor, freeing up another 100bhp.
The X5 Le Mans needed substantial tweaks before it could safely deploy that horsepower and 520lb ft. The six-speed gearbox and rear differential came from BMW’s M division, the suspension was lowered and race-spec springs, dampers and anti-roll bars fitted. The brakes were full race items located within 20in BBS magnesium rims shod with 315/35 tyres at the back, and 275/40s at the front. There was neither anti-lock nor traction control. The cockpit was barely changed.
“There’s a roll cage around the driver’s race seat, itself equipped with a full harness,” wrote Frankel. “The passenger knows no such refinements and is left to slide around in a standard seat with a conventional seatbelt. It has electric windows, central locking, air conditioning and even a sunroof.
“How futile is this car? Sensationally so. Its engine would fail every emissions test, making the car unusable on the road, while its 2200kg weight (not to mention its sky-high centre of gravity) means it would be utterly hopeless as a track machine.”
A few days before Andrew Frankel had his passenger ride around the Nürburgring in the X5 Le Mans, its driver, Hans Stuck, had been asked totry to break the eight-minute barrier around the Nordschleife.
“His out-lap was 8min 6sec, it rained on the second lap and the car broke on the third,” reported Frankel. Fortunately, there were no such problems on Autocar’s hot lap.
“We set off, Stuck revelling in the engine’s incredible torque spread, using as little as 3000rpm before wanting the revs up to 8000rpm between changes.
“On the near flat-out run up the mountain from Bergwerk to the Karussell, he is dazzling and effortless; entirely within himself, yet utterly committed. The X5, so big and slow in the tight turns, suddenly feels fluid, almost agile and very, very quick. We hit 150mph in fourth, skimming across the puddles, Stuck’s will stepping in when simple grip runs out.
“Right in the most difficult section of track, we run into a wall of fog. The sum total of Stuck’s reaction to such potentially cataclysmic weather is to say: ‘Ah. Fog.’ He never mentions it again.”