So this is based off the Wright J5 Wirlwind, but its 7 Pistons to Emulate the Radial Truck. Comes in separate pieces: Block, Seven Cylinders, Exhaust System, Intake/Supercharger unit, Crankshaft Pulley, V-Drive. Everthing is keyed and there will be some clean-up to be done for perfect fitment. This is not an easy model to build I wont lie, getting the exhaust to line up is difficult, but if I can do it... Assembled deminsions of the engine @1:24 are as follows OD ~56mm Depth 56mm.