As every fan of classic American oval racing knows, Offenhauser never, ever built a six-cylinder engine. Well, here it is. The unique piece was commissioned by Chicago-area racer Joe Lencki. 

Lencki, a tough and cantankerous man by most accounts, wouldn’t have enjoyed seeing his engine labeled an Offenhauser. As historian Gordon Elliot White has noted, “Lencki probably would have slugged you.” Still, it was Offenhauser’s brilliant draftsman, Leo Goossen, who supplied the design and drawings. Lencki reportedly had the castings poured, while the machining, fitting, and assembly were performed by Fred Offenhauser and crew at his shop in Los Angeles.

Originally laid out as a two-valver in 1938, the six was updated the following year with a four-valve head. In most details the engine was essentially a 270 Offy, but with two more players—an Offy in all but name. In theory the Lencki should have been superior to a standard Offy four due to its greater valve area and lower piston speeds, but for whatever reasons, things never worked out.

In the engine’s first Indy 500 start in 1939, installed in Lencki’s own chassis (above), the fuel pump failed with 12 laps to go, kicking off a multi-year run of bad luck. Between ’39 and ’47 the car qualified for the 500 a total of five times, but it’s unclear how many of these starts featured the six-banger, since a standard Offy four was often substituted.

Sponsors and liveries on the car included Burd Piston Rings and Blue Crown Spark Plugs, the latter shown here. Drivers included Tony Willman, Floyd Davis, Emil Andres, and Tony Bettenhausen. The car was retired in 1948 but Lencki soldiered on with the engine in various chassis. In 1962 he dropped his six into a brand new Floyd Trevis roadster but the combination was not competitive.

Lencki never hit the jackpot at the Speedway, but he did find a kind of fame as the inventor of an engine oil supplement known variously as Speedway Cocktail, Avblend (purportedly the only oil additive to be approved by the FAA) and Lenckite. Today the stuff is marketed by motorsports tycoon Bruton Smith as zMax, complete with television endorsements by Carroll Shelby.

In 1994, Lencki passed away at the age of 92. The original Lencki chassis and engine were acquired by Don McReynolds, a classic car professional with a genuine devotion to the Lencki story. He restored the car to its 1946 configuration as shown above and vintage-raced it for a number of years. Then, headed into retirement, he sent off the Lencki Blue Crown Special to a new owner at the Mecum Indy auction in May 2009. An assortment of period and modern photos can be found in the slide show below.