how much cam with performer rpm heads?

Here is the spec sheet for the heads..

http://www.edelbrock.com/automotive_new/misc/tech_center/install/6000/60929.pdf

edelbrock valve spring P/N is #5792 ...

here are the edelbrock valve spring specs...

http://www.edelbrock.com/automotive_new/misc/company/10pdf/146-147.pdf