Ted S posted:I think the stock transfer gear probably has 25 teeth. The custom transfer gear ("pinion") must have have 10 teeth. So the new gear ratio would be 25/10 * old gear ratio. 25/10 * 8.33 = 20.83 or about 21:1, just as Daniel measured.
Ted, 8.33 is the ratio of the worm-set. The original external gear set was 27 tooth wheel gear / 25 tooth pinion which gave 1.08:1.
8.33333 x 1.08 = 9 the original total ratio ("old gear ratio")
(25/10) x 9 = 22.5:1
Dave