302 heads for 318

HEI upgrade would help. Contact Trailbeast on the board here, he makes kits.

http://www.forabodiesonly.com/mopar/member.php?u=19664

Like rbdart pointed out, doing the intake and 4v at the same time would be a good idea as you will be removing the intake anyway.

You already have dual exhaust so that will help. A 600 cfm carb should get you what you want, or have RustyRatRod build you a Thermoquad.