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GENERAL INFORMATION_________________________
TERMINOLOGY
The two absolute maximums of linear piston travel in the internal combustion engine are
referred to as TOP DEAD CENTER (TDC) and BOTTOM DEAD CENTER (BDC).
Note that TDC is at the point farthest from the rotation center of the crankshaft, and BDC is
the closest point.
The distance across the piston’s sleeve, or cylinder, is known as CYLINDER DIAMETER.
The STROKE is the distance the piston travels from TDC to BDC.
The cylinder’s DISPLACEMENT is achieved by calculating the cylinder’s volume (by
multiplying (½ DIAMETER) ²*
π
*STROKE), all in centimeters. (NOTE: total engine
displacement is achieved by multiplying this number by the total number of cylinders.) The
end measurement is cubic centimeters, or cc.
