348/409 Chevy


Part Bolt Size Torque to:
Camshaft sprocket 5/16"-18 20 ft. lbs.
Connecting rod 3/8"-24 40 ft. lbs.
*Cylinder head 7/16"-14 65 ft. lbs.
Exhaust Manifold to Cylinder Head (Center) 3/8"-16 25 ft. lbs.
Exhaust Manifold to Cylinder Head (Ends) 3/8"-16 20 ft. lbs.
Fan Blade Assembly to Flange 5/16"-24 15 ft. lbs.
Flywheel Housing to Crankcase 3/8"-16 30 ft. lbs.
Flywheel Housing plate cover 1/4"-20 10 ft. lbs.
Intake Manifold to Cylinder Head 3/8"-16 30 ft. lbs.
Main Bearing Cap bolts (oiled) 1/2"-13 100 ft. lbs.
Oil Pan Drain Plug Special 25 ft. lbs.
Oil Pump Cover to Body 1/4"-20 8 ft. lbs.
Oil Pump to Rear Bearing Cap Bolt 7/16"-14 50 ft. lbs.
Pulley to Balancer Hub 3/8"-24 20 ft. lbs.
Carburetor Nuts 5/16"-24 15 ft. lbs.
Water Pump Bolts 3/8"-16 30 ft. lbs.
Thermostat Housing 3/8"-16 30 ft. lbs.
Oil Filter bolt 1/2"-13 25 ft. lbs.
Starter Bolts 3/8"-16 30 ft. lbs.
Generator Bolts 3/8"-16 30 ft. lbs.
Fuel Pump Bolts 3/8"-16 30 ft. lbs.
Valve cover screws 1/4"-20 20 in. lbs.
Temperature switch 1/2"-pipe thread 30 ft. lbs.
Spark plugs 14 mm 25 ft. lbs.



* Cylinder head torque sequence


Tips for proper installation of heads gaskets.

1) Cleaning. The most important operation of regasketing your engine is thorough cleaning of the cylinder head, block, bolts, and bolt holes. A dirty bolt can throw off torque readings by as much as 20 ft. lbs.

2) Watch bolt lengths. Head bolts on some engines vary in length and it is important that these bolts be replaced in their original location.

3) Head bolts that enter the water jacket of the engine should have sealer applied to the threads. Bolts that enter blind holes should be lightly oiled.

4) Use a torque wrench! Uneven torque causes block distortion and head warpage allowing coolant leak and power loss. The basic tightening procedure is to snug up fastner in stages. Complete last stage with final torque.