hydraulic lifter problems

I know but this is and example of a chevy motor. But my old man was having the exact same problems with his race car. We replace the springs rechecked the valve lash. It ended up being a fuel delivery problem. nothing to do with the motor. He had a weak pump and a stuck float. It would run out of fuel at the top end but when we were checking it in the pits it looked fine. Just food for thought.