ORIGINAL: asupervee72
you can just add a lipo protect, here is one for 20 bucks
http://www.kintecracing.com/Supervee_27_upgrades.html it that is too much there are some 4 dollar ones that buzz or something like that, but the one on that site has a soft cut off and works well with boats, i never had any problems with mine until i blew my esc and it was too close, it may even still work but my new esc's have lipo cut off.
one other option is to time your runs, start at 4 min and go from there
adding one is about the best way to know for sure you are protected
Look to see if you have directions for the escs that came with your boat.. great chance the escs have an LVC built in but they need to be programed to work
and it's very easy to do