I finally got to put a few miles on my '53 3100 this weekend. it has a '56 235 from a car with hydraulic lifters. last year sometime I took each lifter out and disassembled each one and cleaned the gunk out of them, then took my time and adjusted each valve, 1 1/2 turns (i believe) after slop removed. it idled smooth as a watch, but while driving at higher rpm's, approx. 40 mph with 3:50 gears, it got a loud tick. only after slowing down it would go away, then it would come and go intermittently at lower speeds, then it started getting louder and not always going away, until the last run i made it ticks at idle now too. I'm positive it is a valve train noise. has anyone had this situation? any suggestions as to how i should best trouble shoot this? i plan on re-checking valve adjustments first. thanks