I just did a hotcam this week and got the valves dead on. I have gone by the book in the past and it always came out wrong. The problem is that the book isn't accounting for the overlap of the cam. What you have to do is turn the crank one way or the other just a little to get the lifter at its base point then tighten until no up and down movement of the pusrod then I always go 1/4 to 3/8 turn...the book always says 1/2 which is too far in my experience.

 

thanks for all the help. i will try the valves tomorrow then. do 1.6 rockers effect this any? i was putting a half a turn