Hello, I have built many big chief 622, 632, 706 BBC engines. Most of them with sheetmetal or cast tunnel rams with 2X4 4500 carbs. I use Erson or Comp cams mainly and most of the time custom grinds. Here is a grind I use often for a 622, 12 Degree, 2X4, dry sump, natrually aspirated drag race engine, corrected dyno figures for this engine are 1260HP & 925ft/lbs. Cam is mechanical roller, 4-7 swap, Duration @ .050": INT288/EXH308, Lobe Lift: INT.495"/EXH.475", Lobe Separation Angle: 114. Thanks.