JayBee's got a XXXS and the ratio is 1.83. Jay- take your spur gear size(88) and divide it by your pinion(21) that gives you a 4.19. Take that 4.19 and multiply it by the Losi's ratio of 1.83 and you will get the final drive ratio of 7.6685714 or about 7.67. The other gear I mentioned was using a 23 tooth pinion. Or 88 divided by 23 which equals 3.826. Then multiply it by the 1.83 and you get 7.0017. The main reason a lot of guys use 64 pitch gears is to give themselves more ratio's to get closer to whatever one they want. Also, once you get used to getting your final drive ratio, then you can ask a TC3 or a X-Ray driver what their final drive ratio is and you know how to gear your car. A 88/21 combo on your car is way different than the same gears on a X-Ray or a TC3. Confused still? Just find the fast guys at your track and ask them to help you find the right ratio and they should be glad to help you.
Brant