318 Advice

Hey everyone,
Just recently got my '76 Duster a few months ago and joined the forum recently as well. I need a little advice in regards to performance please. I plan to drive on the street and for the Duster to have some snot to spin the tires and get up and go. However, like to cruise to the beach (~50 miles) and run around town as I plan to use it as a sunny day daily driver. Here are my specs:

318 rebuilt w/ 302 heads 5k miles ago
new Mopar Performance Electronic Ignition,
Mopar Air Filter/ Valve Covers,
Edelbrock 4 barrel 500 cfm Performer Carb,
new Ignition coil, ballast resistor
new radiator, water pump, timing chain, oil pump, and bearings
Magnaflow exhaust.
8 1/4 rear and 904 trans
-as per previous owner's ad.

So I'm not sure of the gears in the differential but I feel that it could have a lot more power (or a gear change). What do you recommend for more power...headers?...cam?...a totally new engine!!? hahaa. I don't have a big budget and am looking for advice for a powerful, reliable engine. I really appreciate your help! Hope you have enough info/not too much to make some good recommendations. :)
Thanks,
Trevor


Actually not a bad little set-up.
Biggest problem is weight. 76 Duster is a pretty heavy car.

I think your a little under carbed with the 500. Go to a Edel 600.
Stock manifolds are killing you. Headers or 340 manifolds will open it up.
Little tunning,Timing advance etc will help.
If you like cruising to the beach,dont touch the gears.Otherwise go to a 3:55 gear.