It is a Skyward Engine, made by Picco which make racing engines. I fould some actual pictures of one. Sorry about the small print, these pictures were only copied, not taken by me.

SKYWARD MODEL AIRPLANE ENGINE .60 ABC (10 CC)
DESIGNED AND MADE BY THE ITALIAN PICCO ENGINE MANUFACTURER 15
YEARS AGO APPROX.


Specifications

Displacement 10 CC (.60)
Type 2 Stroke cycle, Schnuerle Scavenged, ABC glow
ignition
Crankshaft 2 Ball Bearings
Bore24 mm (.945)
Stroke22.1 mm (.870)
Carburetor 2 Needles Rotating Barrel 8.5 mm (.330)
Piston/Sleeve True ABC Type (Aluminum piston with chromed
brass cylinder)
Compression ratio 9,4:1
Horsepower 1.65
Weight 21.0 oz

If you want the product review by Clarence Lee in R/C MODELLER
magazine (January 1992)