Formula for Displacement
It's Pi (a constant equal to approximately 3.14) times the radius squared (half the diameter of the bore multiplied times itself) times the stroke times the number of cylinders. If the dimensions are in inches, the answer will be in cubic inches. Alternately, if you use centimeters, the answer will be in cubic centimeters.
So that's: Displacement = radius * radius * 3.14 * stroke * cylinders
I hope that this helps.
Steve
So that's: Displacement = radius * radius * 3.14 * stroke * cylinders
I hope that this helps.
Steve
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Joined: Jun 2002
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From: Upstate NY
Right. To make it easy to remember, use .7854, the four numbers in the upper left corner of a keypad/calculator run clockwise. It is PI/4 rounded a bit and is accurate to a small fraction of a cubic inch of displacement. Actually it it is accurate to about .0008 cubic inches in a 350 V8.
It just makes it easy. You don't even need to remember the exact number. It's on the keypad. That's handy for us older folks.
bore x bore x stroke x number of cylinders x .7854 = displacement
Jon
Right. To make it easy to remember, use .7854, the four numbers in the upper left corner of a keypad/calculator run clockwise. It is PI/4 rounded a bit and is accurate to a small fraction of a cubic inch of displacement. Actually it it is accurate to about .0008 cubic inches in a 350 V8.
It just makes it easy. You don't even need to remember the exact number. It's on the keypad. That's handy for us older folks.
bore x bore x stroke x number of cylinders x .7854 = displacement
Jon
It just makes it easy. You don't even need to remember the exact number. It's on the keypad. That's handy for us older folks.
bore x bore x stroke x number of cylinders x .7854 = displacement
Jon
