Seat Correction Angles

On SOHC exhaust valves, use 15 degrees and 75 degrees to narrow seat and 45 degrees to widen seat. On SOHC intake valves, use 15 degrees and 60 degrees to narrow seat and 45 degrees to widen seat. On DOHC intake and exhaust valves, use 15 degrees to narrow seat and 45 degrees to widen seat.