STITT SPARK PLUG
Standard Torque Values

---

---

STITT Spark Plug Company strongly recommends that only a balance-beam style torque wrench be used to achieve these torque values.

---

---

Standard Torque Values For Cast Iron Cylinder Heads
(In compliance with SAE Standard For Spark Plugs J548d)

Spark Plug Thread Size	Required Installation Torque
14mm x 1.25mm (FS-14 External Seat Gasket)	26 - 30 ft. lbs. 35 - 40 Newton Meters
18mm x 1.5mm (FS-18 External Seat Gasket)	32- 38 ft. lbs. 43 - 53 Newton Meters
7/8" - 18 (FS-78 External Seat Gasket)	50 - 60 ft. lbs. 68 - 81 Newton Meters

---

Standard Torque Values For Aluminum Cylinder Heads
(In compliance with SAE Standard For Spark Plugs J548d)

Spark Plug Thread Size	Required Installation Torque
14mm x 1.25mm (FS-14 External Seat Gasket)	15 - 22 ft. lbs. 20 - 30 Newton Meters
18mm x 1.5mm (FS-18 External Seat Gasket)	28- 34 ft. lbs. 38 - 46 Newton Meters

---

---

Conical/Taper Seat Torque Values For Cast Iron Cylinder Heads
(In compliance with SAE Standard For Spark Plugs J548d)

Spark Plug Thread Size	Required Installation Torque
14mm x 1.25mm	7- 15 ft. lbs. 9 - 20 Newton Meters
18mm x 1.5mm	15- 20 ft. lbs. 20 - 27 Newton Meters

---

Conical/Taper Seat Torque Values For Aluminum Cylinder Heads
(In compliance with SAE Standard For Spark Plugs J548d)

Spark Plug Thread Size	Required Installation Torque
14mm x 1.25mm	7- 15 ft. lbs. 9 - 20 Newton Meters
18mm x 1.5mm	15- 20 ft. lbs. 20 - 27 Newton Meters

---