According to the Tamaran Flying Club, the 80 4C engine is an upgrade of the 60 4C engine. The 60's bore was increased, but the overall outside dimensions remained the same. This increased the power by about 20 percent. The 80 4C engine is recommended for an airplane that requires a 60-size engine, but the 80 4C will give the aircraft more power.
The 80 4C engine has a bore of 27 millimeters. Its stroke is 22 millimeters. This ratio gives the engine a displacement of 12.6 cubic centimeters. The weight of the engine is 580 grams, without the muffler.
This engine is a single-cylinder, four-stroke, overhead valve design. Four-stroke means it has four cycles, which are intake, compression, power and exhaust. The engine has an intake and an exhaust valve in the head. Valve timing, or valve opening and closing, is controlled by two camshafts, which are gear driven off of the crankshaft. As a very sophisticated engine, it has lifters and push rods and the valves have springs, keepers and rocker arms. The engine uses a carburetor to supply the air/fuel mixture.
The engine idles at 2,700 to 3,000 rpm. The working rpm range is from 7,000 to 12,000 rpm. The redline rpm, or the point at which the engine self-destructs, is 13,000 rpm.
A variety of propellers can fit this engine. Some common sizes are 14 by 6 to 11 by 8. Propellers are sized for spinning diameter by pitch. A 14 by 6 spins in a circle 14 inches in diameter. The second number is pitch. Pitch is how far the propeller would move as if it was being screwed into a piece of wood, per revolution. Therefore, a 14 by 6 has a spinning diameter of 14 inches and would move forward 6 inches per revolution. An 11 by 8 propeller has a spinning diameter of 11 inches and moves forward 8 inches per revolution. The recommended weight of the airplane for this engine is from 2.5 to 4.5 kilograms. Any less and the engine is too big for the airplane; any more weight and the engine is too small for the airplane.