First rotate the motor 2 revolutions. It IS better to have the cam a little retarded, like a worn chain would make it later on, then to have advanced cam timing which will run badly. Keep it on the retarded side, when it comes to cam timing. Initial timing means static IGNITION timing at let's say 6 degrees BTDC, like on an old Ford. Then the vac. advance comes in to play. Norm K.