The present invention provides a process for reducing abnormal combustion within a combustion chamber of the engine. The process can include simulation of the piston-driven internal combustion engine with oil droplets from the crankcase entering into the combustion chamber. In addition, the oil drops entering into the combustion chamber can be simulated as hot spots, as can simulation of fuel combustion within the combustion chamber. A probability of pre-ignition for at least a portion of the simulated hot spots as a function of the simulated fuel combustion and the simulated hot spots within the combustion chamber can be calculated and based on the calculation a combustion chamber parameter can be altered such that pre-ignition within the combustion chamber is reduced.