Download PERFORMER RPM BUICK CYLINDER HEADS For 1967-1981 400-455 Buick V8 Engines INSTALLATION PROCEDURE Installation is the same as for original equipment cylinder heads. Consult service manual for specific procedures, if necessary. Be sure that the surface of the block and the surface of the head are thoroughly cleaned to remove any oily film before installation. Use alcohol or lacquer thinner on a lint-free rag to clean. Apply oil or suitable thread lubricant to head bolt threads and the underside of bolt heads and washers to prevent galling and improper torque readings. Use thread sealant on any bolts that go into coolant passages. Torque top row of bolts to 110 ft./lbs. and bottom row of bolts to 100 ft./lbs. in three or four steps, following the factory tightening sequence (See Figure 1) . A re-torque is recommended after the initial star-up and cool-down (allow 2-3 hours for adequate cooling). Other Assembly Tips: When installing the sparkplugs and exhaust manifolds, be sure to use a high temperature anti-seize compound on the threads to reduce the possibility of thread damage in the future. Do not exceed a torque of 25 ft./lbs. on the intake manifold bolts and lubricate the bolt threads prior to assembly. NOTE: Torque sparkplugs to 10 ft./lbs. Do not over tighten sparkplugs! If short reach plug is used, poor performance and possible engine damage may occur.