to preoil: for a BB, turn crank to TDC #6 compression & preoil one bank then back up the dampener 3/4 of a turn (#8 TDC) & preoil the other bank (cut a strip of paper 17.082" or go by the rotor). for a SB, turn crank 90 deg (1/4 turn) BTDC #1 compression (might be partial slits on dampener) or a strip of paper 5.694" & preoil pass bank then turn dampener to 20 ATDC #6 compression (use the timing cover marks to measure the extra 5 degrees) & preoil the drivers bank. EDIT Dave Hughes wants me to use .100" preload on my circle track hyd cam. I was surprised that he wants that much but he has forgotten more info than I know.