You need to degree your new cam when you install it.The cam manufacture may have advance built in the grind,or the timing chain and or timing sprockets,and key way may be off a little.You are only guessing if you don't degree the cam when you install it.There are several ways to advance or retard the cam,they sell a cam sprocket that you can move to set it where you want,or buy a crank sprocket with several different keyway's to set it with.In general if you advance the cam you will increase the power at a lower rpm,and if you retard the cam it will move the power up the rpm range,BUT there are always trade off's in doing this.Go to comp cams web site,they have a ton of info there,and here is a link as to how to degree the cam.
http://www.compcams.com/Technical/In.../Files/145.pdf