It's not an easy topic and books are filled with information on cam timing, lobe centers and duration. A VERY basic description is here.
http://www.muzzys.com/articles/lobe_centers.html
Make note of use of the word SHOULD. It most certainly doesn't always work this way, hence dyno tuning is a good start... or if you have a very accurate Butt dyno that isn't put off by power kicks and sound.
Cam timing is effected by duration, intake, exhaust, head flow, valve sizes and of course where you need the power. I used the word need because pushing power up the RPM range is next to useless.
Oh and never play with your cam timing unless you know where in the duration your valves hit your pistons!
Daniel.