Anodizing works to a point. But its the water jacket and water passage area thats what he is talking about more than the outside of the intake. Anodizing will not last very long by itself in that type of environment.
Watching the PH level, and using a zinc anode in the cooling system works, as well as using the new antifreeze made for aluminum radiators and engines. This stuff is prob set at the correct PH to not corrode anything. Get 50/50 ready to go mix so as to not screw up the pre set PH.
I also sandblasted this passage on my intake, then coated the inside with an aircraft fluid resistant epoxy primer. Tough as nails when baked on. No problems.
