im currently trying to sort a problem with a 420 , it has new cams ,rockers and lifters fitted. all lifter heights /lash caps have been set to factory specs.the problem is after running the car during the day and letting it sit o/night ,the lifters that are loaded by open valves bleed down o/night and are fully compressed in the morning causing a rattly engine. this happens ONLY IN THE LEFT CYL/HEAD??????. lifters have been changed multiple times and still no change . has anybody else come acros this before.