if it's truly low budget, start with a good core magnum 318 or 360, something that just at most needs a hone/rering....deck the block to get the pistons .015 or so in the hole (much easier with a 318) and use the thin Mr. gasket head gaskets. then get the roller cam reground to similar specs as mine, hughes #1110 valve springs and junkyard 2.2L retainers, summit headers, and an eddie RPM air gap with a 600-650cfm carb. you'll have 300-330 solid HP for about a grand....