Ideally you want to setup for initial timing first. The best way (to me) to do this. Is to get the distributor (not a dizzy) in and hookup a vacuum gauge (manifold vacuum). Make sure the vacuum advance on the carb is NOT connected for any of this. Set the idle where you want it, say 750 rpm. And MAKE SURE your carb is setup properly, t-port sync, no vac leaks and such. Or the carb can up the RPM on its own, causing confusion about whether the initial timing is increasing RPM or the carb is. Then start with something conservative. Say 10 degrees. Slowly bring the initial up. If the RPM and vac goes up. Keep going, making sure to reset the idle to your start idle with every adjustment. If you don't bring the idle back down. Then of course the vac gauge will read high. So resetting the idle is very important. You also want to make sure you aren't getting into the mechanical advance on the distributor. Some distributors can start their mechanical advance at 1000 RPM or less. If you are into the advance, it will screw up your initial timing. If you have to. Lock the mechanical advance out so you can get a proper reading. Once you hit max vac on the vac gauge. Back it down 1-2 degrees. Lock it down. Remember your initial timing.
Next step? Hot start. By now the engine should be very hot. Shut the engine off. Leave it for five minutes. Start it again. If it fires right up. You should be ok. Let it run for a few minutes again. Then shut it off again. Leave it for ten minutes. Start it again. If it fires right up. You should be ok. What you are testing here is the "hot start". That is, how well the engine cranks with a lot of initial timing and a starter that's heat soaked from the exhaust running right past it. This test is very important if you have headers. They can cause MAJOR heat soak into the starter. And if you run too much initial timing. The starter won't work proper. OR it might even kick back. Never a good thing. If there is hot start problems. You will need to back the initial down. I suggest 1-2 degrees at a time. You don't wanna lose too much initial timing.
Once you find your good initial. Then you know what to time for your total. MOST small blocks like 34-36. It's uncommon for them to fall out of this area. And it's usually the result of better combustion chamber heads (ie more efficient) or power adder. Or whatever else. So once you know your initial, say 20 degrees. Set your distributor advance for 14-16 degrees, usually all in by 3000 rpm. This is another most common thing. Although some guys run shorter or longer distributor timing. The best way to test total timing, is a track. Set it for 34 degrees. Record MPH/ET. Up it to 35 degrees. Record MPH/ET. Set it for 36 degrees. Record MPH/ET. Whichever one you get best MPH/ET on, is better. If it's best at 34, you could even try going down to 33/32 and see if it picks up. If it's best at 36, you could try 37 or 38 and see if it picks up.
As always. LISTEN for pining/detonation. Not something you should run into on your build. But always something to listen for when setting timing. Usually after I do a tune up like this (carb adjustments, new timing, etc) I also like to get a fresh set of plugs. The constant dicking around with stuff can foul the old plugs. And for a whopping 2 bucks each. It's an easy thing to change to help keep the car running as best as possible.
IDEALLY you want the MOST timing possible at the crank itself (initial) possible. The less mechanical advance you have. The better. The most initial possible will give you the best low end power. When I adjusted my setup and went up to 22 initial. The car was a whole different beast. It ran like a scalded dog. Way better idle. Way better throttle response on the low end. Just a much better tune.
That's the procedure. As for whether your distributor can be adjusted or not? I have no idea. Some of the mopar style distributors need to have the weight slots welded up. My setup (firecore) has the adjustable weights, there's little screws you tighten down. Super simple. Just use the adjustment keys, or a proper size drill bit:
14° = .130” or 3.3mm or #30 drill
16° = .149” or #25 drill
18° = .167” or #19 drill
20° = .184” or #13 drill
22° = .202” or #7 drill
24° = .225” or 5.7mm or #1 drill
26° = .240” or 6.1mm or B drill
28° = .260” or 6.6 mm or G drill
And set it from there. It will depend on your distributor, yours might not be able to do this. One thing you might as well check while setting up the distributor. Is the reluctor gap. Should be .008, butttt as long as you're "near" that, you're ok. lots of guys end up between .007 and .010. Make sure to use a brass feeler gauge to do this.
That should pretty much get you there.
EDIT: Some edits for **** I forgot cause it's late and I am doing six things at once. Also I might have left some small details out. Other's may chime in with them.
