1,791 Posts. #3 · Nov 22, 2003. assumin you have adjustable rocker arms, set the first cylinder at tdc compression stroke, and if you have hydraulic lifters tighten the adjusting screw untill you have no vertical movement of the push rod when you try to move it up or down, spinning doesnt always give you accurate adjustment. then turn the. Stock, the Ford camshaft for a wide range of 300 I6 trucks is 192/268 degrees. The most important thing when choosing a camshaft is making sure it matches the type of driving you plan to do. Shifting all of the performance to the high end of the RPM range doesn't make a lot of sense for a street-driven 4.9, given that you'll sacrifice the I6's.