you should be running 35 wt in the front and 30 wt in the rear. If you lower your chassis a bit it won't be as top heavy and shouldn't flip as much, but if you are going to fast in the turns anything is going to flip. Just some advice, if you are looking for a truck that has good handling I wouldn't have chose the Rustler, I would go for a T4 or something, Just my 2 cents.

Chris