This is the LRP ZR.30 Spec. 2 Monster Truck Engine with Pull Starter. FEATURES: LRP XTEC crankcase constructed of T6 aluminum, black in color Aluminum body slide valve LRP XTEC carburetor with 9mm venturi SG (pilot) type 14.0mm/10.0mm bore triple turbo scoop crankshaft Lightened piston constructed of high silicium alloy ABC cylinder liner construction "A"lloy piston with "B"rass cylinder liner that is "C"hrome plated Extra strong aluminum knife-edge shaped connecting rod with double bushings Ninety day limited warranty (non-European countries only) INCLUDES: LRP ZR.30 Spec. 2 Monster Truck Engine with Pull Starter, standard glow plug, tapered cone, parts list, decals, exhaust gasket and instructions REQUIRES: Fuel with 25% nitro content, 2-stroke model car fuel Exhaust system depending on application, Associated Factory Team Muffler (ASCC6672) and Header (ASCC6676) recommended Air filter, plug wrench and track equipment SPECS: Displacement: .30 cu in (4.92cc) Exhaust: Rear, round Bore: 19.20mm Stroke: 17.00mm Number of Ports: 5+1 (5x transfer, 1x exhaust port) Power Output: 4.12 PS* Max RPM: 33,200* Weight: 15.2oz (430g) Distance Between Mounting Holes Same Side: 0.87" (22mm) Distance Between Mounting Holes Opposite Side: 1.5" (37.5mm) Height/Bottom of Mounting Tab/Top of Cylinder Head: 3.8" (97.5mm) Distance from Pull Starter to Front Bearing: 3.4" (85.5mm) Distance from Pull Starter to End of Crankshaft: 4.6" (116mm) Width at Mounting Tabs: 1.7" (43.5mm) Width Below Mounting Tabs: 1.2" (31.2mm) Diameter of Exhaust Outlet: 0.75" (19mm) including gasket Carburetor Settings: Mid Range, 2.25 turns from closed Main, 2.75 turns from closed *Power Output and Max RPM may vary depending on fuel, exhaust system and tuning jxs 4/16/09 ir/jxs