On road project...need a little help.

[Big House]

Ok, I finished converting a Nitro Super RS4 a while back. I ran it using a MM and the 7700 motor. With that combo, I killed the battery (3S1P A123 9.9V) I was using to run it. I figure I over amped the battery. My question is this, I have a 3100kv Medusa 36/60 on the way, and I am going to mate it with a 3s or 4s battery, but I cannot get the calculator to give me the correct speed. Can someone help me out?

One other question, would a 5lb car be to much for a CMS-7700 if powered by a battery that can feed the amps it might want? I want to see 50ish speed. Thanks