Savage or Emaxx?

[Serum]

You have got a 51T spur i pressume (comes with the .21's and the .25's)

these are the housings i was talking about. if you insist on getting aluminum cups too, get them from 7075 aluminum. The C8019 is tough as nails. (for only 5-6 bucks each)

About gearing;

this might be usefull. Use 1- 1.1V per cell and the wanderer kv-charts to do the math with and you will be pretty close..