This is the HPI K4.6 High Output Pull Start Engine for the HPI Hellfire, HPIC1050. Composite body slide valve carburetor High flow 2-stage foam air filter Rear exhaust Two year limited warranty HPI K4.6 High Output Pull Start Engine with air filter assembly, cold R5 glow plug (HPIG1504), rubber exhaust gasket and instruction manual Fuel: Car blend with 20-25% nitro content Track Equipment: Glow starter, fuel tubing Displacement: 0.28 cu in (4.59cc) Bore: 18.6mm Stroke: 16.9mm Practical RPM: 3,100 - 39,500 Maximum Horsepower: 2.95 hp @ 38,000 rpm Maximum RPM: 41,000 Carburetor Bore: 9.0mm with 8.0mm and 8.5mm reducer Distance Between Mounting Holes Same Side: 0.83" (21mm) Distance Between Mounting Holes Opposite Side: 1.5" (38mm) Height Bottom of Mounting Tabs to Top of Cylinder Head: 3.8" (97mm) Width at Mounting Tabs: 1.8" (45mm) Width of Crankcase Below Mounting Tabs: 1.2" (39mm) Distance from Front Bearing to End of Crankshaft: 1.2" (30mm) Distance from Pull Start to Front Bearing: 3.4" (83.1mm) Distance from Center of Engine to Front Bearing: 1.7" (44mm) Distance from Center of Engine to Pull Start: 1.5" (38mm) jxs 4/20/06 ir/jxs &