I just installed a freshly rebuilt 460 BBF TT for my 74 Hallet. The motor idles well, seems to run fine, but the lifters have always sounded like they are solids when they are hydraulic. In addition, they bleed down with in several minuets after shutdown. The cam lifter kit is and Isky matching system Cam 311-TB Hyd. cam lift in .293 ex. 272 Valve lift in. .515 ex .475 dur in. 274 ex. 260 Lobe center 114 The lifters are Isky 423HY. I have been looking for help from Ron at Isky and he has been great trying to help get this problem solved. Thus far we have changed the oil to Brad Penn 50wt, changed out the lifters a second time, have adjusted them six ways from Sunday, and have been checking the oil filter for any signs the cam could be coming apart. Anybody have any ideas??