[Christ]

Originally Posted by pgfpro

I guess I should have been more specific.

In my post I was referring to two engines of the same design and a average piston speed.

An engine with a 85mm stroke @ 2400rpm will have a mean piston speed of 22.31 ft/second.

This same engine at 6500rpm will have a mean piston speed of
60.42 ft/second.

Now according to Willard W. Pulkrabek book "Engineering Fundamentals of the Internal Combustion Engine" the average combustion flame speed of typical modern SI engine will have a flame speed mean of 82 ft/second @ 1000rpm.

At only 3000rpm the flame speed will increase to 246 ft/second.

As engines rpm increases the intensity of turbulence, swirl, squish, and tumble all increase, resulting in a faster flame speed.

Also with a modern fast-burn combustion chamber engine you will see a 95% burn at 45 degrees crank angle @ 3000rpm.

So you obviously know your stuff on this... knew you did, by the way.

Small displacement long stroke, or high displacement short stroke? (Opinion) (Number of cylinders fixed to 5, for the sake of removing a variable.)