Hubert Schillings, of Germany, designed several miniature engines from 1970 to 1980. Configurations vary from 1-cylinder aircraft engines to 2, 3, 4, 6 and 8-cylinder inline and V-type engines for both aircraft and automobiles. Most of his engines were machined from aluminum bar stock, but a few were machined from magnesium.
The 4-cylinder inline dual overhead cam (DOHC) engine has cylinders in a row vertical to the crankshaft. Each cylinder has four valves (two for intake and two for exhaust) to improve performance and efficiency. Two camshafts operate the valves. One camshaft operates the intake valves and the other the exhaust valves, thus “dual overhead cams.”
Typically, Schillings used belts to drive the cams rather than gears, but rarely enclosed the belt drive system in a housing as is seen here. It is not known how many of these 4-cylinder DOHC engines he produced. This engine, which was completed in 1975, is 11”-long, 6”-wide, 6”-high, and weighs 7 lbs. 2 oz.