BMW Reveals One-Off M5 'CSL'

Munich celebrates M5's quarter-century with 580bhp M5

By SimonSaid / Thursday, 29 October 2009 / Loading comments

The M5 has been with us for 25 years now, and BMW has marked the supercar-bothering super saloon's anniversary with this heavily-modified track version, which they describe as "the M5 CSL we never built". And as it's a one-off prototype, it looks like they're still not going to.

The Martini-esque 'M Sport' colours wrap around a carbon fibre roof and remodelled front bumper, the latter taking its new shape to make way for a secondary oil cooler. The M5's 5.0-litre V10 has its capacity upped to 5.5-litres with a longer stroke, and the car also gets a carbon fibre manifold with an enlarged air box.

The net result of these tweaks has not been officially released, but when the car was revealed at BMW's Nürburgring-based prototype workshop, M-Sport's head of development Albert Biermann reportedly suggested a rather impressive 580bhp. That is a gain of 73bhp over the standard M5, and torque is also claimed to be up to around 400 lb ft.

Weight is down by 50kg to 1780kg, mostly achieved with that carbon fibre roof and a thorough strip-down of the interior. We're told the back seats are gone, along with much of the trim, and the comfy front seats are replaced with racier carbon fibre jobbies. But despite the decrease in weight and increase in power, the suspension is apparently pretty close to standard, with altered mapping for the variable dampers the only tweak deemed necessary.

Helping to cope with the power hike and the demands of harder driving is a modified version of the seven-speed Getrag double clutch gearbox from the M3, with paddle and stick shifters.

At this point the precise performance figures are not known, but racing driver (and top German female pilot) Claudia Huertgen apparently took the modified M5 around the 'Ring in under eight minutes, clocking speeds of over 180mph.

Sadly there are no plans to bring the car into production at the moment, as BMW is focusing its development efforts on the next M5. Unfortunately, there's little hope that any of what we see here will influence the new M5 when it emerges - all reports suggest the next version will be down-sized to a turbo'd V8 in the quest for a 'greener footprint'. But for now we thought you'd enjoy a few snaps from the M5's 25-year and thorougly un-green past.