need to learn about camshafts....

First read this
http://www.hotrod.com/techarticles/engine/hrdp_0804_small_block_mopar_engine/viewall.html

Then
http://www.hughesengines.com/TechArticles/5basiccamguidelinesformagnumlahydraulicrollercams.php

The combo you have may be real close to what you want.