The internal ratio is 2.0 and on my car I run 114/26 gears. The motor should stay in the same position if the total combined pinion size and spur size stays the same. So for example with 40 pinion and 100 spur you would get a ratio of 5.0 and 50 pinion 90 spur 3.6. Not sure what gear sizes in general are available as I never run stock but you should be able to get it low enough.