ERA 569- I know several people who would disagree with you about Vermeesch being the foremost authority on FE engines. I also know of several people that had him build engines who were very dissatified with the results. I doubt if he has ever actually built an FE engine with his own hands. I have met and spoken with him several times over the last twenty years and always found him to be a salesman, P.R. type guy with superficial knowledge of the FE engine.
DWISDOM-Hydraulic lifters should have 0 lash. Check your
oil level, as too much or too little can effect hydraulic lifters along with any air in the
oil system. The second thing to do is check your lifters for leak down and the easier way would be for you to install new lifters to see if that cures the problem after checking the block to see if it had been drilled for solid lifters and the
oil feeds to the lifter bores have been sealed. If not, your lifters are are most likely bad, you are getting insufficient oil to the lifters or
your valve train geometry is incorrect in some fashion. Listen to George Gessford he can help you rule out the possibilities so that your problem can be solved, give him a call, I know he is a hands on type guy, and he has some very knowledgeable guys working for him.
wt