'68 318 to carbed Magnum 5.2: Check my checklist

No argument about the heads-I was only saying that having the new heads inspected for proper installed height, guide tolerance, checking the seats, plus a decent cleaning would be advisable. As far as breaking in a roller cam...it's not needed. The whole purpose of breaking in a flat tappet cam is to work harden the face of the lobe and lifter to one another so they don't dig in. With stock spec roller cams, this process is unneeded due to the hardness of the lobe material and the roller on the lifter. They don't need to be, nor is there any value added (for the cam) by following the break in steps for a flat tappet cam. Now, that being said, if you replace the rings and recondition the cylinders, they'll need to be broken in and proper ring break involves varying the manifold vacuum and engine loading at varied RPMs...which is why many engine builders like to break in engines on dynos because they can vary the load placed on the engine. What I used to do with roller cam engines after making sure there were no fuel/oil/coolant leaks would be to have a friend ride with me and drive around town up and down hills...seemed to work well for the ones I had part in building.