Pelican sells an oil fitting that goes between the block and the oil lines that feed the cams that is a little smaller internal diameter that is standard on newer cars than 84s that helps to boost oil pressure at idle. A number of people including me, have put them in.
Found it top of page this link
http://www.pelicanparts.com/catalog/shopcart/911M/POR_911M_ENGcam_pg1.htm#item4