In this study, we aimed to realize a parametric determination of the convective heat transfer coefficient of a gasoline engine on both the in-cylinder and jacket sides. The combustion products have been determined as a function of excess air coefficient. Cylinder temperature and pressure have been calculated with a simplistic model based on the First Law of Thermodynamics. The in-cylinder heat transfer coefficient is evaluated by using two different expressions; one a specific form of Annand's equation and the other the Woschni equation. Newton's convective heat transfer equation has been utilized to obtain the heat transfer coefficient between the engine block and the cooling water. This process is based on some temperature measurements at various locations in the cooling space, as the distance between the tip of the temperature sensor and the inner cylinder surface is varied for each location. We determined values of both coefficients for various engine parameters. (c) 2005 Elsevier Ltd. All rights reserved.