Bolts with threads used to run ground wires from frame seen them hole left rear last angle or left middle or wherever harness has ground also studs with nut on them go 4 corners to set intake down on two long bolts must go in thru bolt hole
The year, make, model and engine info would help.
24 ft lbs lower intake 115 inch lbs exhaust
take all the wiring and hoses loose from the top of the engine, and you might have to remove the valve covers. then just loosen the intake manifold bolts
Install the lower intake manifold to the engine. Apply sealer, GM P/N 1052080 or equivalent, to the lower intake manifold bolts.Install the lower intake manifold bolts. Tighten the bolts in three steps:TightenTighten the bolts on the first sequence to 8 N·m (71 lb in).Tighten the bolts on the second sequence to 12 N·m (106 lb in).Tighten the bolts on the final sequence to 15 N·m (11 lb ft).I this is what you are looking for.GMmechanic@gmail.com
Try Retightening intake manifold bolts first...............
remove the intake and exhaust manifolds. there are bolts that attach them onto the head and there are bolts near the carburetor that attach the intake manifold to the exhaust manifold.
tbi engine top end is different from carb engine top end. on a carburated engine, the intake and heads use 90 degree angles for intake mounting bolts. on a tbi engine, the intake and heads use 75 degree angles for intake bolts. you can choose one of these three options: entire new engine. intake manifold designed for tbi heads but utilizes a carb mounting flange on top or tbi manifold to spread bore or square bore adapter
you can as long as you use your TBI heads if you want to use the vortec heads with TBI you will need a special intake manifold or a carb manifold with a adapter to mount your throttle body to the carb manifold heres some more info TBI heads will mount to the vortec block TBI intake manifold has 12 bolts vortec intake manifold has 8 bolts
Cylinder Head bolts 65 ft/lbs=Intake Manifold bolts 30 ft/lbs==Exhaust Manifold bolts 25 ft/lbs=
Its a bit of a job because it is held on by the same bolts as the intake manifold, and the easiest way is to remove them both, otherwise the rusted exhaust bolts holding the tubing to the manifold is the worst.
It's under the intake manifold, between the engine and the firewall. 2 bolts, and you have to get to it from underneath the car.
behind the engine right by the back of the intake manifold only 3 bolts the hold it the the block