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Old 04-05-2020, 01:11 AM   #9 (permalink)
Frank Lee
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Originally Posted by California98Civic View Post
How do you calculate/track that while driving? Is there a formula? Seems like you'd need a variety of piston and stroke data as well as RPM.
Get the stroke then online calculators can tell you the rpm range that 1000-1200 ft/mn piston speed is. If your car has a tach you are now golden. If not then you need gear ratios and tire size and another online calculator to spit out the ideal speed range in top gear. Incidentally most of my cars don't have tachs so that is how I did it, and they usually calc out to be in the 45 to 50 mph area.

Stroke differences are how a large engine can be putting along and a tiny engine can be screaming and they will both be at the same piston speed and optimal efficiency range.

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