Originally Posted by
cdwilliams1
A FDR of 4.0 is generally the starting point. On the TC4's stock spur (72t) that would be a 45t pinion. Ask around the track though and play with the final drive calculator on the VTA website.
Originally Posted by
JesusFreak
Guys:
Sorry to but in. I asked in another VTA thread and haven't been able to get any good info. My son and I are setting up a TC4 chassis VTA car, all the stock stuff. What size pinion(s) is typical to use with the stock main gear on the TC4 Club Racer car? Our local track is a nice sized paved track with a good mix of straights and turns.
Thanks for any advice!
Lee
Not sure about the TC4, but a 45 tooth pinion won't fit a TC3 (similar if drive train) without mods to the motor mount and chassis. You'd be better off getting a small spur from the get go. That way you could even switch to 64 pitch before you invest a bunch into 48 pitch gears (unless you already have them). I find the working range of gear ratios for the several tracks I race at to be between 3.2 and 3.8 FDR. If you have to work with 48 pitch, Robinson makes 55 and 52 tooth spurs that will cover that range. 64 pitch is more flexible and there's a bunch of combinations that will work. You just have to do the math (Spur/Pinion) x 2.5 = FDR on your car with consideration of what will actually fit.