Formulas

  • Gross valve lift is the cam lift multiplied by the rocker ratio.
  • To figure your cams overlap; add the intake opening event to the exhaust closing event.
  • Torque x RPM / 5252 = Horsepower
  • Centerline is the distance in crankshaft degrees from TDC to the center of the intake lobe.
  • Valve Lift = Lobe Lift x Rocker Arm Ratio (Evo - 1.60, Shovel - 1.425)
  • Lobe Lift = Valve Lift / Rocker Arm Ratio (Evo - 1.60, Shovel - 1.425)
  • Distance from Cam Nose to Cam Heel - Base Circle Diameter  Lobe Lift
  • Overlap is the distance in crankshaft degrees that both the intake and the exhaust valves are open (at a specified amount e.g.: .053"), at the same time.