Small Block Ford Intake Torque Sequence
So we got that 5-OH up an running and swapping out that POS Autolite 2bbl carb. Time to put on that new manifold and get things torqued down. First off if you have them make sure you follow the manufactures instructions (Edelbrock, Holley, Weiand, etc) for the proper procedures. You will need a few things including the "Nuts, Bolts and Gaskets" as they say. Don't forget the gasket sealer(s) torque wrench and this page. My preferences for gasket sealers on the race cars are Hylomar (Permatex Version) for intake ports and a light coat of High temp RTV sealer for the water jackets and end seals. It's also a good idea to coat bolts that enter the water jacket with some Permatex or similar bolt sealer. For the Small Block Ford I have NEVER used end seals they seem to just squirt out at some point. I like a nice thick bead of RTV at that sealing point.
Small Block Ford Intake Bolt Torque Specifications
18 Ft/Lbs - Aluminum Heads
22-25 Ft/Lbs - Iron Heads
Do the torque in 2 steps, first just hand tight, second with the torque wrench.
IF you do have a spec from the manufacturer follow that. Make sure threads in the head are clean and in good shape. For the SBF one nice thing you can do is use studs for the intake manifold. This is a really nice treat as it helps drop things on without miss-alignment or other intake manifold and gasket issues. In all cases make sure you use the correct length bolts which includes room for washers.
Make sure you follow the sequence in a couple of steps, worry about this more on old and aluminum manifolds. Cast Iron is much more forgiving if you are unfortunate to have to use a boat anchor of an intake.
Some Common Intake Manifold Tips
If you have an old used manifold, before installing it, check for cracks, leaks and the threads in the thermostat housing (often a problem area) and the threads in the bolt for the distributor clamp. You don't want to find out you have to toss in a Helicoil or other insert while it's on the car. For the T-Stat housing and Distributor claps it's nice to use studs if access permits.
Test fit your manifold with gaskets (no sealer). Make sure it looks like it will align. Milling heads and decking blocks can make things not align properly and cause leaks.
Use good sealers, do not use silicon around intake ports, just the water ports. Some folks like to use the end seals, I typically toss them and use a bead of silicon on the front and rear seals of the manifold. Do it in the way you are most comfortable with. If tossing the end seals make sure things are totally clean an oil free.
Their quite a few different intake gaskets for the SBF, check to make sure all ports (Water, Gas, Exhaust, etc) align with BOTH the Cylinder Head and the Intake Manifold.