Valve Seat Correction Angles
Using a 75-degree cutter, adjust exhaust valve seat width so valve contact surface extends to edge of head. Using a 75-degree cutter below, and an 11- or 12-degree cutter above, adjust intake valve seat contact area to center of valve head. Valve seat width should be approximately .06" (1.5 mm) after refinishing. See Fig 1 and Fig 2.