The lvc limits the current when the battery voltage gets to a certain level in order to stop it from dropping below that level.

This normally only ocures under heavy accelleration so when your at top speed and the voltage of the pack is rebounding because of the reduced current draw of crusing at top speed the voltage will be higher than the lvc and thus it wont do anything that will affect your topspeed.

Also if your getting instant flips perhaps you should adjust the weight balance in your car further forward and lower the cars ride height.
Even add some weight the nose of the truck can help keep it down.