you've may have seen these before.
ILF = internal loading factor= 1+S/2R
confusing, but it means this,
do the addition last:
(stroke / 2x rod length) + 1
so for a 455:
(4.21 / 2 x 6.625) + 1 =
(4.21 / 13.25) + 1 =
.317 + 1 = 1.317 initial loading factor.
lower is better.
longer rod, shorter stroke=higher rpm limit.
shorter rod, longer stroke=lower rpm limit.
M mass is weight, self explanatory, weight of piston/rod assembly
lower weight= higher rpm limit.
rod strength- the best material you can find/afford= higher rpm limit
but also best compromise between weight, length, and strength,
to work the top and bottom of formula, to get a bigger overall number
you want a biggest possible number above the line, smallest possible number below the line, after it's all summed out- to match the rest of the combination,
the cam, heads, carburetion/induction.,
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