Abstract: A new testing system is developed for internal combustion engine crankshaft torsional vibration.Its working principle,technical features and measurement results are also presented.A test of a turbo charged diesel crankshaft torsional vibration is made.The system realizes digital testing,improves the testing accuracy and makes the result much more a reality because PC and parallel data interface are used.

Key words: crankshaft, torsional vibration, measurement technology, parallel data interface, personal computer