It's about metals that don't like rubbing against each other.
If you have factory cast iron roller cam and swap in a billet cam, the original gear material is no longer compatible.
Swap a cast one for a cast one and you can use factory style cheaper gear.
That makes alot of sence now lol I gotta check on that then cause I planned on using my original intermediate shaft I may have to buy a new one. I'm using a lunati voodoo cam hydraulic flat tappet.
