the tank where the intake manifold would be with the hose coming off? i assumed that hose was an air intake...did that tank hold fuel and air in it? also - you may be right about the piston rings, just seems unlikely unless nitro burns super easy....a diesel has ballpark 400-600 psi of pressure in each chamber, and 20:1 ratio for ignition of fuel...that seems unlikely without piston rings of some kind...do RC cars have piston rings? with the oil - i didnt see an oil pan ...the motor probably runs slow enough that it doesnt overheat and ruin bearings...he has the assembly lube in it...i wish the video was in engine so we could understand what all the parts are he was putting on...perhaps it doesnt need oil and the assembly lube is enough to keep it going - oiling every session perhaps