OK, your looking to upgrade the 318 to run a bit better without getting crazy on this weekend toy. Gotcha! I'll start with some simple things that will help a lot and carry over for any upgrades later. From top to bottom;
An open air cleaner. I myself also like a air filter lid like a K&N extreme set up.
The carb maker is up to you. Edelbrock or Holley. But I would use a vacuum secondary set up.
For a Holley, I would look at a 600 - 650 CFM carb at the largest. My choice style would be a 4150 series because it has a metering block in the secondary side.
For a Edelbrock, it would be the 650 Thunder series AVS because the secondary air door is tune able with a set of screw drivers.
For an intake, a dual plane is what your going to need.
From Edelbrock, there is the LD4B, an older and very capable intake, the Performer that is flexable on carb selection (spreadbore capable) and the RPM. If you choose the air gap understand that driving in the chilly/cold weather will require long warm up periods. If it is really cold out, the choke will constantly reactivate. Choose the regular RPM with the heat port.
Weiand has the Action plus which is also excellent.
Headers into a 2-1/2 exhaust should use an "H" pipe to conect the two sides.
Mufflers are kind of like ice cream. Everybody has a fav. So this is hard to recommend. But via your description, I think that you'll like the Dyno Max turbo mufflers.
Your ignition should be a min., an adjustable vacuum advance. MoPar has these distributors if hours is not adjustable. A MSD 6 box or equal should run. A good multi spark set up is an excellent investment.
This leaves the cam and it's assoc. hardware, converter and gears to be decided. So that leaves me with, what axle ratio are you willing to live with?
3.55, 4.10? Other?
Is your trans an overdrive? Or regular 3 spd auto?
When you know what axle ratio your going to run, this will help with the cam and converter selection.
The year engine you have suffers from low compression not so easily fixed. While a piston replacement. Milling the heads down is a quick fix though getting it to a respectable ratio may have a flip side issue. If you have to mill the head a lot, the intake may have to be milled as well. While generally not a problem to do so, what you end up doing is creating an intake just for THAT engine. And the. Any intake change will require a trip to the machinists shop. I'd like to avoid that.
