What sealant works best for sealing an intake manifold?

I like Blue Hylomar for the intake gaskets themselves, particularly around the water jackets.

I use Ultra-Black for the front and rear to the block.

I like FelPro marine for gasket and ultra-black silicone for the front and rear of the manifold (looks clean). Sure you can also use the orange copper silicone but I hate the clean-up required to get the engine looking like new.

I have a new system that is working great. Fixed my oil milkshake problem on my intake leak too.

Fel-pro marine gaskets- then spay them down with permatex ultra copper in the spray can. Follow directions- let it dry until it's tacky, then install. Then a bead of permatex ultra black silicone RTV on the front and rear instead of the rubber or cork end seals. Works GREAT!