How does one Select Valve springs?

i know cam selection has alot to do with what you will be needing. It seems seat pressure seems to be the most import aspect, but i was more curious as different springs have different installed heights, open heights, and open pressure. is there a limit or range that we shoot for when building 302 based heads?
 
igotyofire said:
i know cam selection has alot to do with what you will be needing. It seems seat pressure seems to be the most import aspect, but i was more curious as different springs have different installed heights, open heights, and open pressure. is there a limit or range that we shoot for when building 302 based heads?

What I have done in the past is select a cam, then ask the cam designer what springs are recommended. There are alot of details involved in spring selection, and I know that for what I am building it is not that big of a deal.
 
Not to steal the thread but what would would be good valve springs for the E cam, for Windsor Jr. heads and 1.6 rockers. Thanks or maybe someone could just tell me the o.d.? or any specs i need to know to get some valve springs? I wokrk at Manley so i can get new springs for like half price. Thanks