Major automobile engine components are subjected to wear and thermal stress due to high temperature during combustion. Fins are used to increase the heat transfer rate of an I.C. Engine. In an internal combustion engine, the chemical energy of the fuel is converted to thermal energy to give a mechanical work as output. There is a large amount of heat is liberated to the combustion of fuel in which only a few amounts of energy is converted into useful work (60%-80% approx.) and the remaining energy is wasted. This heat is first conducted to engine cylinder and dissipated to air through extended surface called fins. In an air-cooled engine, the low rate of heat transfer is the main problem. To avoid this, the engine's fins are modified by changing the geometry of the cooling fins. All materials are showing a linear distribution of temperature alongside the length of fins. Also, the hexagonal shape fins increase the heat flux by converting the fin geometry from a rectangular shape to hexagonal and thus reduce the wear of engine parts and knocking of the engine.