BMW CSL Coupe Hides A Whole M5 Underneath

A mashup of a BMW E39 M5 and two E9 coupes is for sale on Bring a Trailer, featuring a hand-built fusion of classic coupe styling and E39 M5 performance. The result combines 1970s slim-pillared style with 21st century M-car performance.

The transformation wasn’t a simple body swap. According to details from an original build story, the M5’s upper structure was removed, the floorpan was shortened by roughly 8 inches, and an E9 roof was grafted onto the chassis.

To keep everything looking right, the front arches were widened by around 2.5 inches and the rears by about 4 inches. Much of the fabrication work was carried out in Romania, where skilled craftsmen shaped custom panels by hand, and for a lot less cash than it would have cost in Germany.

The finished product is equal parts homage and hot rod. It wears CSL Batmobile-inspired aerodynamic pieces like the roof spoiler and tiny front fender fins, Hella driving lights, 3.0 CSL badging, as well as a Porsche paint finish.

Inside, the illusion starts to crack in the best possible way. The modified M5 dashboard remains, joined by heated Recaro seats, dual-zone climate control, power windows, and a Pioneer touchscreen.

The car is powered by the donor E39 M5’s rebuilt 4.9-liter S62 V8 producing a claimed 426 hp through a six-speed manual gearbox and limited-slip differential.

KW adjustable coilovers and retained M5 brakes help keep everything in check. The car features custom wheels wrapped in Continental SportContact 7 tires, which replaced the E39 M5 wheels seen during the build’s early media appearances.

The project was created by German outfit MKO, founded by enthusiast Michael Oberhauser around 10 years ago. It effectively merged an E39 M5 with parts from not one but two E9 CS coupes.

The result is a machine that combines 1970s slim-pillared style with 21st century M-car performance, making it a unique and impressive addition to any classic car collection.