Excessive consumption of fossil fuels has exacerbated global warming and led to an increase in air pollution levels in the environment. The increasing oil demand prompted recent research to explore the future application of alternative, eco-friendly fuels for diesel engines. Jatropha biodiesel has been produced from JCO, using heterogeneous catalyst (CaO) through transesterification process. In this study, the performance and emission characteristics of an engine powered by a Jatropha biodiesel blends have been investigated. The application of response surface methodology (RSM) coupled with Taguchi method for optimization of engine input parameters is promising approach to derive the most accurate optimized models for output responses. Input parameters such as biodiesel blend, load, CR, and FIP were selected, experiments were designed as per L18 orthogonal array in Taguchi, and CCFCD L20 design matrix for RSM methodology. Injection timing is an essential engine characteristic, which has a considerable effect on the ordering emissions. If injection is done early, the starting air temperature and pressure are lower, which means the ignition delay will rise. The ignition delay may begin at any time after the injection begins, resulting in somewhat increased temperature and pressure initially but which then rapidly declines as the ignition delay progresses. The optimal setting of engine input parameters is recorded at 270 bar fuel injection pressure, compression ratio of 18, 7.61 kg load, and 25% blend of Jatropha biodiesel with diesel for optimum BTHE, BMEP, BSFC, Pmax, CO, and NOx emissions. Experimental results are compared with optimum output responses and deviations are found within the accepted range of errors.