Could this idea work ? Did other guys did this ? 318 infos
2bbl will give up power to 4bbl, hod rodding is a series of compromises, each to their own, overall with your plan you should gain over stock, here's a stock low cr long block with 4bbl xe262h cam and headers for 282 hp @ 5000 rpm 340 tq @ 3500 rpm, give you an idea what some basic mods will do.
318 Long Block Bolt Ons - Tech Articles - Mopar Muscle Magazine