I keep breaking rocker arm bolts, help please!

Of course it won't. Bolts are bolts. There are all kinds of bolts, grade 2, grade 5 (which is MOST of what is in your average engine) grade 8 and special grades.

So the listing for "any" grade 5 bolt in 5/16 size, with course threads and lubricant is..........................NOT 30ft lbs

http://www.engineershandbook.com/Tables/torque.htm