I have gotten some good input from you all, so I'm going to keep asking for opinions on the parts for my project.

I'm converting my 1999 7.4MPI into a Carberated engine.

I have a set of Vortec heads at the machine shop having larger valves install per Dennis Moore's book.
The cam that I will choose should have my engine max out at 5000-5200rpm.

We run 75% in fresh water and always end in fresh water. I believe if I have an aluminum intake hard anodized, it will be fine.

So which intake manifold should I buy???

Holley with 0-5200 rpm range
Edelbrock Performer 0-5500 rpm
Edelbrock Performer RPM 1500-6500 rpm
Edelbrock Performer RPM Air-Gap 1500-6500 rpm

I am leaning toward the Air-Gap being that it is the latest technology, but I thought I would ask you all.

Thanks!!!

I know several people that run the Air Gap and are
very happy with the results good overall performance

I've been researching this, and in your case I'd probably pick air gap. My case would be 100% salt, so I may have to go another direction.

I like the Weiand Stealth intake manifold (Idle-6800 RPM) for marine small-block Chevrolets, and it's an inexpensive intake as well.

Air Gap!

Thanks to all, the Air-Gap it is.

Air Gap