I have the zz4 camshaft with hydraulic rollers. I purchased a Summit HEI distributor pn SUM-850001R. I read that a melonized cam gear drive is required for steel roller camshafts. What the heck does that mean? Do I need to purchase a different ditributor gear for my Summit distributor? What does "melonized" mean? What happens if I run it with the "hardened steel" gear drive?