This BGX-1 is the engine of choice for those Giant Scale Modelers. The BGX-1 35cc Engine was designed as a lighter, more powerful, less vibration, and more compact alternative to the converted chainsaw gasoline engines. One drawback; fuel economy is better with the chainsaw engines, and fuel is less expensive. The BGX-1 includes an engine mount that mounts to the firewall in the same bolt pattern as the backplate-style engine mounts that come with SuperTigre"s models S2000, S2500, and S3000(K) engines. You can directly replace any of those engines with the BGX-1 without redrilling your firewall. This engine is covered under the O.S. 2-YEAR WARRANTY. FEATURES: Two crankshaft ball bearings Side exhaust Ringed piston Schnuerle porting (AKA Schnuerle scavenging) Two chamber expansion-type muffler (included) Safety prop nut assembly Remote Needle Valve . INCLUDES: Expansion-Style Muffler w/Adapter and Screws Backplate-Style (radial) Engine Mount (OSMG2308) One Hardware Bag w/screws, blind nuts, lock (split) washers to mount the engine One Safety Prop Nut Assembly (OSMG6689) One Woodruff Key (OSMG9364) One #8 Glow Plug (OSMG2691) One Set of Instructions, Poster, and Decal One Remote Needle Valve and Hardware to mount the needle valve . SPECS: Construction: Aluminum and Aluminum alloys Displacement: 35cc (cubic centimeters) or 2.13 cubic inches Bore: 37.3mm (1.47") Stroke: 32mm (1.26") Max Output: 4.1 PS, 4.04 HP at 10,000 RPM Practical RPM Range: 1,500 - 10,000 RPM Crankshaft Thread Size: 3/8-24 Height: 142.5 (5.61") Width: 60.5mm (2.38") Width neglecting the engine mounting flanges 74mm (2.91") width between the centers of the mounting holes 103mm (4.05") diameter of the backplate engine mount Length: 129.5mm (5.10") from the back of the engine mount to the front of the drive washer Weight: 1340g (47.3ozs) without mount or muffler 1045g (49.6ozs) with the mount and NO muffler Suggested Prop Sizes: 18x8, 18x9, 18x10, 18x11, 18x12, 20x8, 20x9, 20x10 High Speed Needle: 1 - 1.5 turns out from fully closed Low Speed Needle; 1 - 2mm gap between the needle and spray bar at full throttle (looking down the neck of the carb) REQUIRES: Fuel with 5%-10% nitromethane and 18% MINIMUM lubricant content (20% is recommended). ALL 5%-15% fuels we carry meet these requirements. ir/jl updt lmm 3/27/09