Simple upgrades are easy and mostly eye candy of your flavor. Pick a 600 cfm carb you like and know how to work on. A Performer or LD4B (IIRC) is very good on the 318. Upgrade your ignition and recurve the distributor. If your not willing to spend on a new converter, your cam should stay under 218@050 & that kind of depends on what gear ratio and tire size you want to end up with.