In the paper the possibilities of a Rapid Compression Machine in the investigation of the fundamental processes in IC engines have been presented. The test-stand design, principles of its control and basic operational features have been discussed and compared with the parameters of the test facilities of similar type currently in use worldwide. A short evaluation has been performed of its functionality and possibilities of application in the research on thermodynamics of injection and combustion processes. The evaluation pointed to the possibility of variation of the parameters and variables in the RCM. The main parameters and operational indexes of the Test-stand have been presented along with some examples of the achieved results from the investigations of engine internal processes