In Diesel engines quality of combustion is depending on the formation fuel-air mixture. A high-quality of formation for combustion is achieved by mixing of pulverized fuel drops and the air inside the cylinder. In this matter, injection parameters such as timing and period of injection, injection pressure and the number of the injection beams affect quality of combustion and mixture formation.The main purpose of this work is to find the optimum injection advance angle for traditional diesel and diesel-ester blends in a direct injection (DI) compression ignition engine. Tests are conducted on an air cooled single cylinder, high pressured (600–1600 bar), plc controlled research engine. Engine torque, brake power and brake specific fuel consumption values associated with each of these fuel blends are collected under certain operating points. A piezo transducer is utilized to detect in-cylinder pressure and an incremental encoder for the relative position of the piston top to the dead center location.In the light of the obtained values, no negative impact was observed on the performance with the addition of ester up to 20% by volume and these results are concordant to the results of the other researches. It is seen that at suitable injection advance ester blended fuels capture the peak pressure value in less time for engine as given in the literature. Similar to the prior studies, biodiesel addition to diesel fuel raises heat output at premixed combustion phase, reduces the combustion at diffusion phase. On the other hand, when the injection advance had been closer to TDC, it caused a decrease in pre-phase peak value and an increase at the values of diffusion phase.