The Mono-Aircraft Corporation (Don Luscombe), which had bought several Aircat engines, was dissatisfied with its reliability and availability. Mono-Aircraft Corporation persuaded Velie Motors Corporation of Moline, Illinois to essentially copy the Aircat. Velie received Approved Type Certificate No. 4 covering its M-5 engine on 22 Jun 1928. LeBlond, which then owned the rights to the Aircat, sued Velie for patent infringement and was awarded damages. After the demise of Velie, the engine line continued under the name of Lambert Engine and Machine Company.
The Velie M-5 was an air-cooled 5-cylinder radial with a 4.125" bore, 3.75" stroke and 250.6 in³ displacement. Initially producing 45 hp at 1,750 rpm, it was upgraded to 55 hp and finally 65 hp at 1,900 rpm. It had a 5.2:1 compression ratio and 240 lb weight. M-5 cylinders were cast from nickel-iron with integral cooling fins. A cast aluminum alloy cylinder head with aluminum-bronze valve seats was employed. Cylinder barrels and heads were held to the crankcase with four long studs. The two-piece crankshaft ran on three ball bearings. Two Scintilla magnetos and a Stromberg NA-R3 carburetor were employed.
For details of this engine restoration, see:
(Text credit: Aircraft Engine Historical Society)