O.S. MAX 30VG (P) Engine (L-OS13960) When the engine in your Monster Truck is just not quite enough, yet you are restricted by the size of the mounts (21 size), the new 30VG could be the answer to your prayers. This engine is designed to pack the largest amount of power into the smallest possible crankcase. Supplied with the P style crankshaft. Specification: Weight: 360g 12.70oz Displacement: 5.0cc 0.298cu in. Bore: 18.5mm 0.728in. Stroke: 18.2mm 0.717in Power Output: 3.0PS@28000 RPMPractical RPM: 4000-36000