From the Technopower website:

The Technopower radial engine, originally based on the Armstrong-Siddeley Genet engine of the 1930s, took over 5 years of design and development work (with continuing detail refinement). The result is a unique, aesthetic, practical, scale, flying engine of considerable engineering interest. These engines are fully functional, multi-cylinder, 4-stroke, O.H.V., glow ignition engines, each containing over 300 hand-assembled parts. Each engine is assembled, checked, and test run before leaving the factory in Santa Ana, CA.

Standard engine specifications:

Overhead valve, 4 cycle, glow ignition engines of 7 or 9-cylinder. 1.35 to 4.0 cu. in. displacement. Normal rpm range of 1,200-8,000. Heavy duty crankshaft supported by dual ball bearings. Billet aluminum master and articulated rods. Billet aluminum pistons with ductile iron rings. Hardened steel cams and cam followers. Hard chromed and ground cylinder bores. Stainless steel valves, heat treated, ground and lap seated. Bronze valve guides and cam follower bushings.

Exhibit added: November 29, 2010 - Last modified: April 5, 2023

Presented by The Joe Martin Foundation for Exceptional Craftsmanship