Who else but Mercedes-Benz would have the patience and the commitment, the sheer bravado, to transform an already iconic model—the 300 SL Gullwing Coupe—into a “luxury” Roadster?

When Stuttgart introduced the 300 SL Roadster in 1957, the new model addressed many of the perceived shortcomings of the outgoing Gullwing. The Gullwing’s tube frame was redesigned to accommodate conventional doors, which not only eased ingress and egress, but provided space for wind-up windows, a feature that significantly improved cabin comfort.

The unforgiving high-pivot geometry of the Gullwing coupe’s swing axle was discarded in favor of a low-pivot swing-axle rear suspension, with a transverse coil spring above the differential (linked to the axles by vertical struts) to minimize oversteer. The frame and suspension redesign also facilitated the installation of softer coil springs, which endowed the Roadster with superior ride quality without compromising handling.

The highly developed inline six-cylinder engine was standard-equipped with the competition-proven sport camshaft from the racing alloy-bodied Gullwings, increasing output by 25 horsepower. This propelled the civilized Roadster to impressive successes in privateer racing, including Paul O’Shea’s numerous class wins in SCCA events.

Though it was packaged as a flagship luxury tourer, the 300 SL Roadster was nevertheless a better-performing version of its racing forebear, and it remains the more useable and easily enjoyed of the two models. The convertible SL’s design configuration was so successful that a descendent of the original model has remained in production in one form or another to this day, epitomizing the notion of an automotive legend.

This intriguing 300 SL Roadster is one of the more significant blue-chip collectibles cloistered within the Rudi Klein Collection. According to the data of the Gullwing Group, chassis number 7500173 is one of 554 Roadsters built during 1957, the model’s debut year. As detailed by a copy of a factory delivery note, this Roadster was desirably specified, finished in Fire Engine Red paint (DB 534) over a cream leather interior (1060); and equipped with a Becker Mexico radio, sealed-beam headlamps, instruments in kilometers, and a set of luggage.

Of particular note, chassis number 7500173 is one of 30 examples that were known to be factory-equipped with the iconic competition-derived Rudge wheels, which significantly enhance the car’s build provenance and corresponding value. The Roadster is additionally equipped with the longer-legged and higher-speed 1:3.42-ratio rear axle (in contrast to typical US-bound Roadsters, which were equipped with a 1:3.89 ratio).

A ROADSTER OUT OF SIGHT FOR DECADES

In September 1957 the completed 300 SL was delivered to its buyer, a Mr. Thompson of Kitzingen, Germany. The Gullwing Group Roadster Register displays no data for chassis number 7500173 whatsoever, suggesting the car was not in the possession of active collectors in the niche before it came into the purview of the Junkyard. The Roadster has therefore apparently been removed from the marque community for many decades, and it would surely encounter a warm welcome once properly restored and recommissioned for driving and exhibition.

Stampings indicate that this Mercedes-Benz retains its matching-numbers engine, body, rear axle, and front axles, although the gearbox, number 7500205, appears to have been replaced at some point. The Rudge wheels furthermore display properly matching date codes, cementing the car’s authenticity. The current odometer reading of 17,873 kilometers (~11,106 miles) might well represent genuine original mileage, considering how long the car has been stored in the Junkyard Collection.

For the consummate Mercedes-Benz collector seeking to steward a 300 SL Roadster restoration from junkyard find to showfield contender, there is no better opportunity than the availability of 7500173. Retaining its matching-numbers engine and significant mechanical components, as well as rare Rudge wheels, and originally finished in Fire Engine Red, this intriguing Roadster promises to capture the heart of any marque enthusiast once it has been rightfully rejuvenated to its proper appearance.