While Ole Evinrude — and later Carl Kiekhaefer of Mercury — brought recreational boating to the masses with outboard power in the 1930s, ’40s and ’50s, an industry executive and racing enthusiast changed the game again with his popularization of the sterndrive, also known as the inboard/outboard. Ironically, Wynne was working for Kiekhaefer when he helped develop the first sterndrive engine. According to Mercury’s own history, Wynne worked for Mercury from 1953 until 1958. It was there that Wynne worked in secret on the design of the sterndrive, under the direction of the famous Mercury executive Charles Strang, who actually first conceived of the idea in 1948. Kiekhaefer had originally rejected the concept, so Strang worked on it with Wynne in secret. In 1958, Wynne left Mercury and began assembling a sterndrive prototype out of outboard parts in his garage in Miami. Later, Wynne traveled to Sweden to present the idea directly to Volvo Penta’s president, who liked it enough to reach a licensing agreement with him.
At the New York Boat Show in 1959, Wynne publicly introduced the first Volvo Penta Aquamatic sterndrive, paired with an 80 hp engine block. An enthusiastic boat racer, Wynne also worked with Don Aronow to help build what eventually became the venerable Donzi Sweet 16. Mercury joined the party in 1961, and sterndrives started winning over boaters. Over the next decade, boat-racing enthusiasts began to phase out outboard power in favor of sterndrive applications because the design allowed builders to mount bigger, more powerful engine blocks directly into the hull and couple them with the drive. In terms of horsepower, outboards at the time just couldn’t compete. Soon gasoline sterndrive applications became synonymous with boats, from the family runabout up to the midsize cruiser, and racing would never look back.