1974 318 duster. Can I port/polish these heads and get enough power out of them?

Hey all. I bought this duster and it already had some goodies. Holley 4 barrel street avenger carb and edelbrock low-rise intake with a 3" flow master dual exhaust. The exhaust manifolds are the originals, but I can probably change them out and weld them to the 3" flow masters.

Can I take these heads off, port and polish and keep them? I don't have the money to do much, and keeping things cast is really fine with me. I'm also thinking about putting in new piston rings and an oil pan and rebuilding or just servicing the 904 that came in it so it doesn't leak. And then maybe spending some money and making the rear end a sure grip if they make it with the 8.25. Was also going to put a decent cam in it and change everything to where it works right.

Thoughts? I don't have a big budget at all.

318 Long Block Bolt Ons - Tech Articles - Mopar Muscle Magazine

318 Engine Buildup & Dyno Test - Mopar Muscle Magazine

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