break-in oil?

Any oil that contains zinc ,{not many left} like valvoline VR1 racing oil.It states right on the bottle that it contains zinc. Also advance auto parts sells an additive by Lucas that is specifically for break in,especially for flat tappet cams and is "zinc rich" The zinc helps the cam break in during the critical first minutes of initial start up . . . . hope that helps.
I agree zinc is the key to making any flat tappet cam survive a break-in, also as stated above make sure your only using the outer valve spring for the break in..