I'm wondering about top and bottom heat, and effects on oven spring.

As a self taught baker I just sort of worked out what I like, but I can't find much about it in books or on the internet. What settings do people use for their ovens, does increasing the bottom heat increase the spring? Can anyone point me in the way of some good articles or books that may cover this? Or is it one of those things you just figure out. 

Sam