1,488 cc air-cooled, horizontally-opposed OHV four-cylinder engine, Pepco centrifugal supercharger, two-barrel carburetor, four-speed manual gearbox in rear transaxle, independent front suspension with parallel trailing arms and laminated torsion bars, independent rear suspension with swing axles and transverse torsion bars, and four-wheel hydraulic drum brakes. Wheelbase: 82.7"

• Rare “Pre-A” example; restored mid-1990s; from important connoisseur collection

• Period-modified with expertly installed ‘Pepco’ supercharger

• Featured as “The Sleeper” in March 1958 PCA Porsche Panorama

Initially based on relatively humble but highly effective Volkswagen Type 1-based mechanicals, Porsche’s cornerstone 356 model was relentlessly developed, perfected and refined with unparalleled care and determination throughout its lengthy production run. Simply put, the running changes from the 1948 prototype to the final production models of 1965 are nearly innumerable, and while highly documented, they will continue to fascinate and engage the legions of die-hard Porschephiles well into the foreseeable future.

While the 356 was always a premium automobile at its core with startling performance capabilities in factory-stock form, some owners demanded even more. The 1500-powered “Pre-A” 356 Cabriolet offered here is a fascinating case in point. Purchased by Harry Mershimer of Poland, Ohio in 1953 at the insistence of his wife as a more comfortable alternative to the couple’s Pepco-supercharged MG and its almost shocking lack of weather protection, the Porsche soon felt the magic touch of Harry and his considerable machining and mechanical expertise. The MG sacrificed its supercharger, which was deftly transplanted into the Porsche’s rear engine bay with a beautifully engineered installation as if Porsche designed it that way in Stuttgart.

Highlights of Mr. Mershimer’s work include an intake manifold weighing just 19 ounces, which was precision-machined from a 15½-pound aluminum billet, and a pair of beautifully radius-bent intake runners. A simple but very effective two-barrel Holley carburetor originally intended for use with a Ford six-cylinder engine application provided optimal air/fuel mixture, with fuel delivery provided by an electric fuel pump. The Pepco blower was set up to yield conservative and engine-friendly boost levels, topping out at five psi of boost at 5,000 engine revolutions and beyond.

In testament to Porsche’s legendary durability, the blown 356 had already covered an astounding 93,000 miles by the time two testers from the Porsche Club of America’s Porsche Panorama drove to visit the Mershimers and their already-famous car, known as “The Sleeper”. With two on board after individual familiarization runs with Mr. Mershimer, the Panorama testers perfected their launch technique until sub-10 second sprints were made from rest to 60 mph. Reportedly, the then-58-year-old Mr. Mershimer routinely achieved much quicker times in the eight-second range, and few dared challenge him and his trusty “Sleeper”.

Over the next 35-plus years, the “Sleeper” fell out of sight until it was restored during the mid-1990s, retaining its full supercharger installation and the neatly manufactured “Supercharged” rear scripting it wore during Harry Mershimer’s tenure. It was acquired by a noted Porsche collector and enthusiast shortly after its rebirth, and in 1999 he and the Porsche completed the California Mille without issue and with truly remarkable performance. In fact, the current owner reports that this early supercharged 356 delivers performance levels comparable with the final-production 356 SCs built in the mid-1960s. Handsomely presented, complete with its original intake and carburetor and a copy of the highly detailed and engaging 1958 Panorama magazine, “The Sleeper” lives on today as a well-cared-for and highly desirable “Pre-A” Porsche 356 with fascinating early history and a performance surprise to boot!