BMW M6 E24
The BMW M6 E24 -- known as the M635CSi in European markets -- is one of the most elegant and capable grand tourers of the 1980s. It married the svelte E24 6 Series coupe body with BMW M's hand-built S38 inline-six engine, creating a car that could cross continents in refined comfort while delivering performance that embarrassed many dedicated sports cars.
The S38B35 engine was derived from the M88 unit used in the legendary BMW M1 supercar. This dual overhead cam inline-six featured a forged crankshaft, individual throttle bodies, and the kind of engineering attention that only a hand-assembled motorsport-derived engine could deliver. In US specification, the S38 produced 256 hp (European versions produced 286 hp due to different emissions equipment and ECU calibration). The engine revved willingly to 6,900 rpm, delivering a smooth, linear power curve that perfectly suited the M6's grand touring character.
The M6 designation was used in the US market (and later adopted globally), while European cars bore the M635CSi badge. Despite the different names, the specification was essentially identical apart from emissions equipment. The US-market M6 was produced from 1987 to 1989, while the European M635CSi ran from 1983 to 1989.
Power reached the rear wheels through a Getrag 280 5-speed manual gearbox and a 25% limited-slip differential. The chassis was the standard E24 platform with significant M GmbH modifications: stiffer springs, firmer Bilstein dampers, thicker anti-roll bars, and revised steering calibration. The result was a car that balanced comfort and handling beautifully, with enough composure for spirited driving while remaining supple enough for long-distance cruising.
The E24 body design, penned by Paul Bracq, is widely regarded as one of BMW's finest. The long hood, compact greenhouse, and shark-like profile gave the 6 Series a timeless elegance. The M6 added subtle aerodynamic enhancements including a deeper front air dam with fog lights and a small rear spoiler.
Inside, the M6 was thoroughly luxurious, with full leather upholstery, electric seats, air conditioning, and a comprehensive instrument cluster. The M-specific steering wheel and gear knob were the primary interior distinctions, though the overall ambiance was one of understated, high-quality craftsmanship.
Total production across both M635CSi and M6 designations was approximately 5,855 units. The car has become increasingly collectible as enthusiasts recognize the combination of the M1-derived engine, the elegant E24 body, and the hand-finished M GmbH build quality. Clean examples now command $40,000 to $100,000, with pristine low-mileage cars exceeding those figures.
The S38 engine is generally robust but requires regular maintenance. Check for oil leaks (valve covers, oil pan), timing chain condition, and cooling system health. The Getrag gearbox is strong but synchros can wear with age. Rust is the biggest concern: check sills, jacking points, windshield surround, front fenders (behind the wheel arch), and the battery box area. Electrical systems are complex for the era. The digital instrument cluster can fail and is expensive to repair. US-spec M6s with full service history command the best prices.
The M635CSi was produced from 1983 to 1989 (European market) and the M6 from 1987 to 1989 (US market). Total production approximately 5,855 units. The S38 engine was hand-assembled at M GmbH's facility. European cars produced 286 hp while US-spec cars made 256 hp due to emissions equipment. Each car was individually finished at M GmbH before delivery.