Caaarlo wrote:
Hmmm as far as i know, regrinding a cam involves adding material to the stock core first, filling the lobes. Usually done with a welding machine, right ? Once you have done that, you regrind the lobe to the desired profile. If the filling process or hardness treatment were done improperly, then you will experince these sort of problems.
BTW, you got PM.
It is a process that can be done (welding) if you have excessively worn lobes, there is not sufficient lobe mat'l to support the grind being applied, or if there will be interference, or geometry problems once the new profile is completed. In the case of the GT cams, there is plenty of material, lots of base circle diameter, and no geometry issues. As far as I know, there is no heat treatment involved, other than maybe some preheating of the cast iron.
I have never added material to any of my cams for a few reasons. It is a time consuming process (expensive), is not generally required, and can, although rarely, be a problem.
I didn't get your PM, and what are the specs of your cams?