This program is now one of several modules within the comprehensive program LINKAGES described elsewhere on this site. LINKAGES/Engine solves the kinematic and dynamic equations for any slider-crank based internal combustion engine or motor driven compressor. A pressure curve that represents the gas explosion or gas compression is built into the program to simulate that event. The user needs only to input the stroke volume of one cylinder, the crank and conrod lengths, and the masses and locations of the centers of gravity of crank and conrod to calculate all kinematic and dynamic parameters for an assumed constant angular velocity of the input crank of a one-cylinder, or multi-cylinder inline, vee, opposed, or W engine configuration. The crankshaft can be exactly balanced or overbalanced and the effects on shaking forces seen. The force, moment, and torque balance configurations are calculated for any selected engine configuration based on the chosen crankshaft phase angles, number of cylinders, and vee angle(s). The calculated kinematic and dynamic parameters can be plotted as either cartesian or polar plots, and all data may be printed to the screen, a printer, or a disk file that is suitable for import to a spreadsheet program. Data necessary to the sizing of a flywheel for any selected coefficient of fluctuation are calculated.