Even though the operating principles of the internal combustion engines have been the same for 125 years, for compression ignition engines and for 151 years or even more, by some authors, for spark ignition- engine builders have tried and managed to improve their performance. One of the methods used was and still is the use of new materials. Among these materials the ceramic materials have a significant role. The present paper aims to find a calculation formula for the actual motor torque of a classic spark ignition engine and with a ceramic crown piston.