All you guys throwing out all these suggestions before you even know....
-What area of the rpm range he wants to build power in.
-How far is he going to go with his mods. When will he consider his engine mods "done"? Just doing I/H/C/E, or going into engine internals?
No one can give an educated answer without knowing these things. Gdep....you need to have a plan for you engine so that all the parts you buy for it are working together, and not against each other, to get maximum power gains. Having a plan will prevent you from buying the wrong parts and wasting money.