motion ratio help

[Norm Peterson]

Usually, the c/d ratio (using your nomenclature) is within a couple percent of 1.00 with the chassis at its static ride height. After squaring for wheel rate purposes, it's still only 'off' by 5% or so. That's for a car with reasonably stock-ish geometry and wheel offset.

Note also that the FVIC component of motion ratio is slightly variable in both ride and roll modes as the FVSA lengths vary. A rather complicated formula could be written to cover this variability in "c" and "d", but nobody would ever use it outside of developing a spreadsheet or other computerized analysis.



I suspect that most people figure that keeping the theoretical numbers within 5% is close enough most of the time. Then again, I've seen the spring angle correction factor not being squared (it should be), so I hope I'm not assuming too much.

Just for comparison, the 5658, 5660, 5662, and 5664 Moog springs are in approximately 10% rate steps.

Norm