Now get this, I was following GM'* data for replacement of the gasket and they have revised many "wrong torque specs" for this particular motor from the rocker arm bolts to the lower intake to the upper intake. They have updated all of these specs but made a mistake on the upper intake manifold bolts. They claim 18 ft lbs for torque specs. That is dead wrong. When I was torquing them as per "GM'*" published data what I thought was the torque wrench clicking when reaching 18ft lbs of torque was really the upper intake manifold cracking due to excessive torque being applied.