This article presents the development of a geometric model for the full-cycle simulation of a spark ignition engine fueled with a biomass-derived syngas. The engine simulations are carried out in KIVA 4, using a global reaction mechanism. This model aims to predict the parameters that stipulate the engine performance and NO emissions. The domain undergoes a convergence process to select the appropriate mesh size for the simulations. Then, in order to assess the veracity of the results obtained in the simulations, a comparison is made with experimental data reported in the literature. In this way, it was concluded that the developed model successfully predicts the mixing process, the combustion of the gas, the indicated parameters, and the NO emissions of the real engine, presenting admissible differences regarding the experimental results. Finally, with the validated model, simulations are carried out, modifying different ignition parameters, seeking to evidence the engine operation as a function of these variables. The results demonstrate that it is possible to obtain improvements in the engine performance and its polluting emissions, altering the ignition energy, ignition timing, or spark location.