It might come down to what you have to start with. I haven't built one yet, but here is a combo i think would work well, and cheap, too!
One option is a 400 block, 4.375 bore, offset grind a 383 crank to 3.54 stroke, use 7.10 bb chev h beam rods, shelf stock 1.12 compression height pistons for 426 cheap cubes. Add a .590 MP cam, 2 inch x 40 inch headers. Should make 575 to 600 hp, cheaply.