my intake manifold is getting a couple of little rust spots, so i take it that it is cast iron, or steel. Does anyone know of an aluminum intake that would be a direct replacement for the most part that would work with my rochester carb?

You could just glass bead and repaint your intake. I have two intakes and carbs off '89 454 Magnums that are in liike new condition. I believe they are aluminum, but I would have to check. I would sell cheap. Let me know if you are interested in one of them.

well, maybe, i was just trying to figure out if a company like edelbrock or something made a mild upgraded or stock replacement in aluminum. If i was to go through the trouble of pulling that intake off, i wouldn't want to put another steel one back on.

Ive got an Edelbrock performer that Im not using. rogue2800 (at) hotmail.com

would something like that work with my original carb, i'm pretty sure i have a rochester..... how would a mild upgraded intake effect fuel/air mixture, would i have to play with the carb settings or would they be fine as is??

Edelbrock makes a Performer that takes the spread bore carb.
I ran one on my 1989 330HP/7.4.
A K&N filter is also a nice upgrade.
My engine gained about 100rpm on top with these two additions...

Yes, mine is for the Quad. spreadbore.

how do i know if i have a "spread bore" I'm not sure what that means. I just know that i have a '90 7.4L merc, and i've been told that i have a rochester but i have never verified that

Might try to find a Merc aluminum intake with the brass lined water passages. Regular alum intakes will corrode at the gasket mating surfaces. Even in fresh water use.

There aren't too many intakes that match up well to the peanut port heads. Be careful with your selection or you will go slower!