In this study the performance and emission characteristics were compared for a Jatropha B30 blend with that of diesel in a Low Heat Rejection Engine. The engine cylinder, piston crown and cylinder head were coated with a stabilized Zirconia coating using a plasma spray gun to obtain a Low Heat Rejection system. A single cylinder, four stroke, constant speed, water cooled direct injection engine was used for the experiments. The acquired data were analyzed for various parameters such as thermal efficiency, specific fuel consumption, CO, HC, particulate matter and NOx emissions. © 2015 Journal of Chemical and Pharmaceutical Sciences.