you are correct. Easiest argument to make is the aluminum heads expand at a much higher rate (vs temp) than the steel or moly pushrods. I believe cast iron does as well. just not looking it up now. so basically you are making the pushrod seem "shorter" in relation to the distance between the lifter and the rocker (or technically adjuster) so you have more clearance.

Last edited by Kevins493; 12/04/10 03:59 AM.