BMW 328 Cabriolet

Bayerische Motoren Werke was fully a decade old before it built its first automobile. Formed by the merger of two aero engine manufacturers during World War I, the firm found itself casting about for a new purpose, when postwar strictures forbade the German company to make aeronautical components. Accordingly, the company branched out into motorcycle and heavy truck powerplants. In 1923 came the first complete motorcycle, establishing a pattern – opposed cylinders and shaft drive – that would characterize it for all time. The engines were also used in some small German cars. A few prototype cars were built using flat twin engines, but none reached production.

When real automobile production came, it was not with a BMW design but a concept imported from England. Purchasing the Dixi Werke of Eisenach, BMW continued manufacture of the smallest Dixi product, a license-built version of the Austin Seven. The BMW badge was adopted for these cars in January 1929, although Dixi remained part of the marque name for a further six months.

In March 1932 the Austin license was given up in favor of a larger BMW design. This was the 3/20PS Typ AM. It had a 782 cc engine, slightly larger than the Austin-based unit, but with overhead valves. A backbone chassis frame supported independent rear suspension by swing axles and leaf springs, and swing axles at the front. Bodies came from Daimler-Benz at Sindelfingen.

In the spring of 1933, BMW introduced the Typ 303, a 1,173 cc six with tubular chassis. The rear swing axles were replaced by a rigid member, while the front continued independent with transverse leaf spring suspension. The grille was “nierenformig,” kidney-shaped, a hallmark that continues to this day. Up-to-date features included rack-and-pinion steering and hydraulic brakes. A Typ 309 four-cylinder car of 845 cc was also offered.

Growth was rapid. 1934 brought the Type 315, a 1,490 cc car, which was available in 40 brake horsepower triple carburetor tune. This was the first BMW designed by Fritz Fiedler, an engineer formerly with Stoewer and Horch. Fiedler would influence every subsequent BMW model until his retirement in 1964.

The 1936 Berlin Auto Show heralded an important BMW development, the 326. The company’s first four-door sedan, it had a 1,971 cc, 50 brake horsepower engine, and was capable of 72 mph. More streamlined than earlier BMWs, its styling would set the pattern for the marque until World War II. Chassis was a new box-section frame, and torsion bars were now used at the rear. More significantly, the 326 begat several variations that overshadowed the parent model; the 320, a cheaper four-cylinder car, and the 327, a short chassis, two-seat coupe or convertible.

However, it was the sporting 328 that made the biggest news. The 328 had the same 1,971 cylinder block, but a new crossflow head with hemispherical combustion chambers and used short horizontal pushrods to operate opposed exhaust valves from the single camshaft. This gave twin-cam performance with less complexity and lower cost. A twin-tube chassis was used, topped with a two-seat sporting body. Top speed of the standard model was 96 miles per hour, but the renowned British driver S.C.H. “Sammy” Davis clocked 102.16 at Brooklands in a lightweight prototype. Higher compression and ported heads gave even better performance. A streamlined 328 won the two-liter class at LeMans in 1939, and the same car, part of a five-car team, won 1940’s Mille Miglia outright. Just 462 were built through 1939, against nearly 16,000 of the “bread and butter” 326 cars.

Coachbuilder Georg Autenrieth partnered with Franz Eisenlohr after World War I at Karosseriwerke Weinsberg in Weinsberg, Württemberg. In 1921 he left to start his own business, Erste Darmstädter Karosseriewerke Georg Autenrieth, at Darmstadt where he became quite prosperous building cabriolet and tourer bodies for Opel and Röhr. Autenrieth bought into Röhr Automobilwerke, served on its board and supplied a major portion of the marque’s bodies. When BMW introduced the 326/327/328 series in 1936-37, Autenrieth built cabriolets and coupes, including a four-door version for the longer 326 chassis. A sedan version featured a cantilevered sliding door which Autenrieth patented. Other marques to use Autenrieth bodies included Adler and Maybach.

After World War II, Autenrieth built some beautiful 501 and 502 cabriolets and coupes for BMW, as well as Opel’s 1959-62 Rekord. The firm closed down in 1964, after orders from Opel ceased.

The snug and stylish cabriolet body by Autenrieth is very attractive, its teardrop fenders considerably more graceful than those of the more common roadster body. The skirts on the rear fenders exhibit a concentric circle motif, hinting at the wheels they hide. The deep red paint is in excellent condition, a full two decades after restoration, and the tan convertible top is nicely set off with body color landau irons. The interior is done in tan leather with matching carpets, a theme reprised in the luggage compartment, which opens from the top. The spare tire is subtly recessed into the lid, and its uncovered functionality provides nice contrast to the otherwise unbroken lines of the body.

This car was auctioned off by RM Auctions in March of 2009 at the The Ritz-Carlton, Amelia Island, Florida.

80bhp, 1,971 cc overhead valve six-cylinder engine, four-speed manual transmission, independent front suspension with transverse leaf spring, live rear axle with semi-elliptic leaf springs, four-wheel hydraulic drum brakes. Wheelbase: 94.5"

Source: RM Auctions

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