I keep breaking rocker arm bolts, help please!

Wet or dry? Up to you. Arp gives you lube to put on the threads. I don't think a factory bolt 5/16 bolt will take 30 ft lbs dry or wet. The real issue I think is over torque. Nothing wrong with what krazycuda is saying about doing it dry. A lot of aftermarket fasteners give you wet torque and dry torque values. And they can change between lubricants.