formula to calculate engine size?
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formula to calculate engine size? anyone got a clue? so far my best guess is bore x stroke x 25.4? but then my numbers come out a tad high on smaller cube engines and a tad small on larger cube engines.
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From: Upstate NY
Originally Posted by nesikachad
BORE X BORE X STROKE X .7853982 X How many cylinders there are.
Example, SBC:
4 X 4 X 3.48 X .7853982 X 8 ='s CID
OR 4 (squared) X 3.48 X Bla, bla, bla, X 8 ='s. . .
349.84
AKA the good ol 350 Chevy.
Example, SBC:
4 X 4 X 3.48 X .7853982 X 8 ='s CID
OR 4 (squared) X 3.48 X Bla, bla, bla, X 8 ='s. . .
349.84
AKA the good ol 350 Chevy.
FWIW, .78539... is PI/4
Oh yeah, it's counter-clockwise from the bottom left on a cell phone calculator.
Just to clarify the actual formula for everyone. It is the cylinder area times the stroke times the number of cylinders. Area of a circle is pi*r^2 or pi*d^2/4. The pi/4 is where that constant .7854 comes from.
Bore^2/4 * pi * #cylinders = Engine Volume (in whatever units you are using, just make sure to stick to inches or mm so your numbers come out right. Mixing units will mess it all up).
Bore^2/4 * pi * #cylinders = Engine Volume (in whatever units you are using, just make sure to stick to inches or mm so your numbers come out right. Mixing units will mess it all up).
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From: Upstate NY
Originally Posted by Hugger Z
Just to clarify the actual formula for everyone. It is the cylinder area times the stroke times the number of cylinders. Area of a circle is pi*r^2 or pi*d^2/4. The pi/4 is where that constant .7854 comes from.
Originally Posted by Hugger Z
Bore^2/4 * pi * #cylinders = Engine Volume (in whatever units you are using, just make sure to stick to inches or mm so your numbers come out right. Mixing units will mess it all up).
