The two cams pictures are the Leineweber L-61 and an S&S 516. If you look, the L61 makes the 516 look like a shrimp! the 516 is a moderate stroker cam, not a maniac like this one! To install this cam a fair amout of modifications have to me made. the case has to be clearanced for the lift AND the distributor gear has to be thinned out because the lobe hits that too! this was a pain in the ass!!! it took most of the afternoon to get this cam to find its new home, but its ready to rip now!