Wits End With A 318
It is time.......to start with the BASICS
Time to run a compression check, and this gives you a chance to check the plugs which may be FOULED. You can get some idea by listening to the starter. Know what a "normal" cranking engine sounds like? You can hear the individual cylinders labor the starter. An engine with cam/ etc problems (no or little compression) will just "spin."
Next, check the spark AGAIN. First check the coil wire and make sure you have a nice fat blue spark. Crank the engine long enough that you see a nice series of rythmic, multiple sparks, not "intermittent. Then check again down at the plug
REALLY check the timing:
Remove no1 plug, stick your finger in there, and bump the engine 'till it pushes your finger out. LOOK at the marks, they should be "on the way up." Wrench or bump the engine until the marks are say, 10BTC or so. Pull the cap and verify two things:
The rotor should be approaching or "on" the no1 plug tower, and the reluctor should be right at the center of the pickup core. On a small block, the dist runs cw, so you can spring the rotor cw a little against the spring to see better if necessary.
If you have points, you want the points to "just open"
Next DO NOT TRUST what is in the tank. Has it been sitting awhile? How long? Six months? A year? (gag) Longer?
Get some fresh gas or starting fluid. Squirt a little right down the carb.
If you do this right, it should fire as if you parked it last night.