Mugen MBX4-RR Conversion!

[SilveradoHD]

I am about to order the parts right now to convert my MBX4-XR. I will be running a Medusa 2000kv with a MMM ESC and a Airtronics 358 servo. I will be using the cheap zippy packs. My question is, should I got for two 3s, or two 2s, or just go for one 4s,5s, or 6s? This car will not be raced other than drag racing so weight distrubution is really no concern unless it will greatly affect handling with one big pack. Would a 16t be sufficient on a 4s without overheating? What about if I step up to a 5s, or 6s.