These won't really give you more hp, but they are really good and pretty basic mods. Have the lifter valley de-burred, have the oil drain back holes chamfered, maybe have the crank knife-edged (depending on price), and get a windage tray.
Now would be a great time to get a new cam and matching springs. Summit makes pretty good cams (especially for the price). I alway liked the performer intakes, which used to run about $150 online or at swap meets. Holleys are plentiful and pretty inexpensive. You could be into one for less than $100 of you are willing to rebuild it yourself. Look for headers on forums like this or locally. They are pretty expensive new.
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