Is there an easy way to figure out what speedometer gear I need? I've changed tire size and rear end gearing. I'm running 245/60R15 tires and 3.25 rear gears behind a wide ratio trans. This is on my 69 Mach 1. Thanks.
Looking at the gear chart in CJ Pony, it is showing the same 16 tooth gear for both the 3.00 and the 3.25 unless theres a difference in F70-14 and FR70-14 tires? How can that be? The F70-14 tire is 24.78" tall, I'm running 245/60R15s that are 26.55" tall. I'm assuming with the bigger tires I would need maybe 1 tooth larger gear? I'm not that good with math, I just know my speed is about 15 MPH to fast right now and would like to get right with out buying and swapping a bunch of gears.