Ok so I have a savage x that i converted to electric. The bevel gear set on the front got striped so i want to replace it with the bulletproof ones from hpi. So the stock gear set is 43/13, which is hard to find, but ive seen some that are 29/9. What will 29/9 do? Will that give me more torqe like going down on a pinion? And can I only replace one set and not the other since its still good? Thanks for any input.