Mercedes-Benz introduced a new model lineup in 1965 at the Frankfurt Auto Show to serve as a replacement for the Heckflosse or 'Fintail' W111/112 models. The three new W108-Series models consisted of the 250S, 250SE, and 300SE, as well as a single W109, the 300SEL. These new models wore updated styling but their engines were, by and large, carried over from the previous generation but were carefully refined. The fuel-injected 280SE saloon shared its bodywork with the 'New Generation' 280S, while the 280SE Coupe and Cabriolet retained the elegant looks of the outgoing 250SE that had debuted back in 1959 on the 220SE. They initially used the single overhead-camshaft inline 'six' in several sizes, culminating in the 3.0-liter unit, with the numerical model names varying by engine size. As the 1960s were coming to a close, the lack of a V-8 engine in the roster was becoming a hindrance in the all-important U.S. market, so a new 3.5-liter V-8 powerplant, internally designated M116, was developed.
The 3.5-liter version (3499cc SOHC V8) of the 280SE signified a resurgence of larger-engined Mercedes-Benz models, with the ultra-luxurious 280SE Coupe, Cabriolet, and 300SEL saloon models introduced with the 3.5-liter V8 in 1969. An over-square design featuring a cast-iron block and aluminum cylinder heads, each equipped with a single overhead camshaft, with Bosch electronic fuel injection and transistorized ignition, the state-of-the-art power unit produced 200 horsepower at 5,800 RPM. Mercedes-Benz modestly referred to as the 'engine of tomorrow'. Zero-to-sixty mph was achieved in 9.5 seconds and the top speed was approximately 125 mph.
The 3.5-liter V-8 had been developed for maximum efficiency and durability, and delivered an infusion of smooth, turbine-like power, and would yield scope for further development into the 4,520cc 'big block' designated M117 in 1971.
The new W108 model was designated 280SE 3.5, to distinguish it from its six-cylinder counterpart. They sported a 'Flachkuhler' grille that was 100mm wider and 70mm shorter than the one found on its older siblings. The 280SE 3.5 employed all-round independent suspension (double-wishbone front / low-pivot swing axle rear), power-assisted steering, and four-wheel disc brakes. The interior housed leather upholstery, wood veneers and a multi-layered hood, with seating for four or five passengers in comfort. Air conditioning, power windows, and stereo radio were standard equipment.
The 280SE 3.5 Cabriolet was on par price-wise with the expensive 'Grosser' Mercedes-Benz 600 and was predictably exclusive. Only in production for two years, just 1,232 are thought to have been made of which a mere 68 were to right-hand drive specification. Production of the 280SE Coupe and Cabriolet totaled little over 5,000 units between 1968 and 1972 when production ceased. Each example was essentially hand-built inside and out to exacting standards of craftsmanship.
by Dan Vaughan