edelbrock heads on a 318

All in all, yes. They have the potential for the most power, but it's an issue of whether or not your little 318 could use all that flow to its full effect. Remember, the RPM head was designed to go on 340's and 360's. In ported form some even use them on 408 stroker small-blocks. Money aside, the RPM's might be too much for your engine. Intake charge velocity is more important than max flow when dealing with street engines, and the RPM ports/valves are probably too big to keep good velocity at lower rev's, which a 318 needs in order to have decent torque. I'll attempt to lay out all the choices in order of "potential":

Stock 318 heads, pre-1986: Open chambers, small ports, work fine when reworked but don't have the nice closed chambers of later heads

Stock 318 "#302" heads, 1986-1991: Closed chambers, slightly smaller "swirl" ports, probably best option for milder street performance and racing in some cases when well-ported

Stock 360 "J" heads, 1970's to 1980's: Bigger open chambers, larger ports, good option for higher-performance street 318 builds as long as higher-compression pistons are used and smaller 360 intake valves are retained; can be upgraded with larger valves to basically become "X" heads

Stock 340 "X" heads, 1968-1970: Arguably the best LA performance heads, open chambers, big ports, big valves, a bit much for a street-oriented 318

Magnum heads, 1992-2002: Arguably most versatile and efficient small-block heads with best stock low-lift flow (great for a street engine), closed chambers, great potential on a 318 but require some valvetrain mods to adapt to LA (pre-1992 318, 1993 360) block and are a bit tough to find in solid condition

Edelbrock RPM heads: Aluminum aftermarket performance heads designed for the 340 and 360, closed chamber, big ports, big valves, great design but ports too big for a street 318

Indy Cylinder Head 360 heads: Aluminum aftermarket performance heads designed for max-effort barely-streetable stroked engines (at least 408 cubes), you would never need these unless you were doing some serious racing and had to stay with a small-block

Personally I'd go with ported 302's if you can find them, or cleaned up 'J' heads if you can swap pistons.

IF you went with the Edelbrocks, you'd need higher-comp pistons and/or the will to rev your engine really really high to make power (which really annoys me personally, if you want that then go with a turbo 4-banger).