RE: #age for mechanical broadheads
Texasbowhunter is correct. It all depends on your broadhead of choice. As a general rule bigger heads need more KE while smaller heads can get by with less. Swing open or "jack knife" styles require more energy while heads that slide back into posistion require less. 55 ft/lbs is a good basic minimum for the average head, but you really need to make sure you have plenty of KE.