What is the Speed of a Gas Engines Piston?

[outrun]

I know this dependent on displacement/RPM etc. Can someone post and engine and guestimate the piston velocity at its redline rpm throught its downward or upward travel. Thanks-

m/s, mph, kph whatever you like, least I can do is convert this on my own time to my desired unit.

 

[Terry]

Mean piston speed in fpm =
2xstroke in inchesxRPM / 12

Rev limit piston speed=
piston speed in fpm x6/stroke in inches

 

[tamu_man]

You can calculate the average speed (distance over time), but the speed of the actual piston is constantly changing on a sine wave.

 

[outrun]

Thanks, so this is a MEAN value ....

So is the equation independent of or already has the number of cylinders worked in? The reason why I ask is just because your tach says 5,000rpm definately does not mean Cylinder X is 5k. I know the Crankshaft motion caused by other moving pistons tampers with the mathematical system here *lol*

For example I can see this equation working in a one cylinder lawn tractor engine but same for a V6?

 

[Terry]

The equations work to determine the piston speed independent of the # of total pistons. Unless you have a variable/multiple stroke setup!

 

[Shannow]

quote:

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Originally posted by tamu_man:
You can calculate the average speed (distance over time), but the speed of the actual piston is constantly changing on a sine wave.

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only on a scotch-yoke engine.

Throw in a con-rod, and it's not a sine wave.

 

[moribundman]

Piston Speed Calculator