Eric Minoff
Vice President, Head of Department - US
LOT 37
1982 BMW 635CSi "The Observer Coupe" Coachwork by MGA Developments Ltd. VIN. WBAEC7209C8175000
Sold for US$28,000 inc. premiumLot to be sold without reserve
Lot 37
1982 BMW 635CSi "The Observer Coupe"
1982 BMW 635CSi "The Observer Coupe"
Coachwork by MGA Developments Ltd.
VIN. WBAEC7209C8175000
Coachwork by MGA Developments Ltd.
VIN. WBAEC7209C8175000
3,430cc SOHC Inline 6
Bosch Motronic Fuel Injection
182bhp at 5,400rpm
4-Wheel Independent Suspension
4-Wheel Disc Brakes
* A unique, coachbuilt machine
* Originally developed with a retractable glass roof
* Well documented
* A special, one-off BMW Grand Tourer
THE CAR OFFERED
Conceived as a technological showcase and design statement, this remarkable one-off BMW 635 CSi stands among the most intriguing British coachbuilt projects of the 1980s. Internally designated "Special Project M3" by Coventry-based MGA Developments Ltd., the car was created to demonstrate the company's full spectrum of engineering, styling, and prototype-development capabilities. Established in 1979 by Mike Gibbs, MGA provided design-to-production services for major automotive manufacturers, and this ambitious project served as its ultimate calling card.
Supplied new by BMW Great Britain in 1982 and financially supported by The Observer newspaper, the donor 635 CSi was transformed into what was envisioned as the world's first fully retractable glass-roofed grand tourer. Developed in conjunction with Triplex Safety Glass and Tudor sunroof mechanisms, the innovative roof system employed a sophisticated arrangement whereby multiple glass panels and the rear window retracted into a specially engineered compartment within the custom-fabricated tail section. Extensive clay modeling—using some 200 kilograms of clay—was undertaken to refine the design, while structural rigidity was preserved through an integral rollover bar. Under the leadership of former Porsche designer Stephen Ferrarda and electrical engineer Stanley Daniels, the extraordinary conversion was completed in just three-and-a-half months.
Finished in period two-tone grey with bespoke spoilers, side skirts, graphics, and distinctive Centra alloy wheels, the prototype made its public debut at the 1982 British International Motor Show in Birmingham. Although limited-production plans were explored, the complexity of the roof mechanism ultimately prevented commercialization, leaving this example as the sole survivor of the project. Retaining its original drivetrain, the car combines unique coachbuilt design with the driving qualities of BMW's flagship grand tourer.
Following its press-tour duties, the car remained with creator Mike Gibbs until 1993, during which time the retractable roof was converted to its present fixed-glass configuration. Accompanied by an extensive history file, MOT records, and service documentation dating from 1989 to 2023, the BMW benefited from comprehensive restoration and refurbishment work in 2017 reportedly exceeding £26,000. Acquired by the present owner last year and showing just 19,315 miles at the time of cataloguing, this singular prototype represents a fascinating chapter in automotive innovation and a remarkably well-preserved precursor to the panoramic glass-roof concepts that would later become commonplace in modern grand touring automobiles.
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