Speedometer Pinion Gear

matthon said
So if you don't have an existing gear, like me, go by the chart, then once installed why would the math/calc be different?

255/60/15 with 3.91s = 38 tooth gear, which apparently isn't a valid gear in those calcs.

These guys are basing their math on some variables that are just that, variable. So, I'm glad to see he is basing this on a chart/on-line calc. I think that's the best bet.