Rx8 gear and final drive ratios, also consider that it redlines at 9000, so despite the 4.78:1 rear end, the high redline helps stretch out those shift points. Also included is the BRZ ratios. Beyond all of this you have to take into consideration tire size, frontal area of the car, coefficient of drag, shift time, etc, as well as the optimal shift points based off of the torque curve of the vehicle.
http://www.perfectshifting.com/
Tends to be a decent calculator for this.
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2016 Halo FR-S, 2010 Tundra, 92 325i convertible, 80 Mazda 626, 62 Impala