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A predictive, quasi-dimensional simulation of combustion in a spark ignition engine has been coupled with a chemical kinetic model for the low temperature, pre-flame reactions of hydrocarbon fuel and air mixtures. The simulation is capable of predicting the onset of autoignition without prior knowledge of the cylinder pressure history. Near-wall temperature gradients were computed within the framework of the engine cycle simulation by dividing the region into a number of thin mass slices which were assumed to remain adjacent to the combustion chamber surfaces in both the burned and unburned gas. The influence of the near-wall turbulence on the temperature field was accounted for by means of a boundary layer turbulence model developed by the authors. Fluid motion in the bulk gases has been considered by the inclusion of a turbulence model based on k - ε theory while the flame propagation rate was predicted using a fractal flame model.