Rod to Stroke Ratio 2

[jabs86]

Engines designer's who prefer a shorter rod combination use the quick piston movement to their advantage .It's easier to help accelerate the piston when the shorter rod is helping you along.Also pressure on the crank is exerted at a sharper rod angle giving more leverage at that moment.A long rod piston is barely moving it's hard to accelerate a piston when the lack of rod angle means no leverage on the crank.The smaller combustion chamber longer or something that is already moving is easier to push.Both have advantages high piston speed's over all like a longer rod only up to the point where wait outweighs the advantage. To much rod angle at high RPM. beats the hell out of piston skirts.Exhaust action,if you open the EX at 55 degrees BBDC which combination has more blow down time relative to piston position,remembering the effect that SR have at the bottom of the stroke. Reading between the lines is a necssary skill for a mechanic ,fill in the blanks .