A excellent addition to your model, the GF40 from OS Engine combines the economy of a gasoline engine with the power of a 4-stroke.

Features
Offers traditional 4-stroke benefits with the ease and economy of a gasoline engine
Quick, powerful response makes it an ideal choice for aerobatic as well as scale models
Perfect for scale aircraft, with a deeper exhaust note that mimics the sound of full-size aircraft
Features the GT33’s mounting bolt pattern and mount-to-drive hub distance
Outstanding fuel economy — runs on a mix of engine oil and standard gasoline
Rear-mounted carb designed by O.S. & Walbro
Lightweight ignition module accepts NiCd, NiMH, LiPo or LiFe battery power
Muffler and integral backplate mount included
Backplate features an integral choke rod guide
PCV (Positive Crankcase Ventilation) system recirculates blow-by gas and oil waste for a cleaner engine and environment

Specifications

Benchmark Prop	18x8-12 - 20x8-10
Plug Type	CM6 Spark Plug
Recommended Fuel	30:1 - 50:1 gas/oil mixture
RPM Range	1,800 - 9,000 rpm
Cylinders	Single
Ignition Weight	3.4 oz (95 g), 3.4 oz (95g)
Bore	1.57 in (40mm)
Displacement	2.44 cu in (39.96 cc)
Type	4-stroke gasoline powered airplane engine
Width	3.3 in (83.7mm)
Length	4.7 in (118.5mm) from backplate to drive hub
Engine (Only) Weight	2.64 lb (1.2 kg)
Stroke	1.25 in (31.8mm)
Crankshaft Threads	UNF5/16-24
Height	6.2 in (157.2mm) bottom of mount to top of cylinder cover
Carb Type	Rear mounted Walbro
Prop Range	18 x 8 - 20 x 10, 18 x 8 break-in
Muffler Weight	4.0 oz (113 g), 4.0 oz (134 g)