I Bought A 428 Industrial Block W/ 406 Head With Cj Valves And It Seemed Loud. After Running It W/out Beating On It I Noticed Alot Of Noise Which I Thought Was Just The Solid Lifter Cam But Found Out That Three Tops Of The Valves Were Pancaked Flat. What Causes This. Bad Springs, Too Loose And They Needed Adjustments?