Changing Motor Encoder numbers with change in internal gearing.

So I recently changed the internal gears in our drive base of our robot from Normal gearing to high speed. We know that this makes the motors 60% faster but now the Autonomous is going to be all messed up. Is there a number we can multiply the Motor Encoder distance by in order to correct for this change? I tried to do the math and I ended up with a number that I doubt(0.625). Could someone with more experience check my number or if you have dealt with this before and know the number could you provide it?

google search “vex ime ticks” : result
Click product info under technical specifications and it will give your the numbers for ticks per revolution based on gearing.

Thanks! That should help!