hv maxx and lipos

[_paralyzed_]

Also, stock gearing will be wayyyyy off. The velineon at 3s is spinning 38850 rpm. The 6.5 at 4s is spinning 50320 rpm. You would have to gear down for that rpm difference alone. Add to that the increased diameter of the revo wheels and you will have to gear wayyyy down.

You should learn how to use this tool > http://www.scriptasylum.com/rc_speed/top_speed.html

It's a speed calculator made by this forum's own BrianG. You simply plug in the appropriate values and it will show you the speed you will get with different tire sizes/voltages/gearing etc. It can be found in the brushless section here at Rc-M stickied at the top.

The kv (rpm/volt) of the 6.5 is 3400. Plug in your values and shoot for 35-40 mph, and that will tell you the gearing you need.