Timing Curve on 360 in an RV

The whole point of ignition timing is to light the fire at the right time to get the pressure in the cylinder to peak at the optimum crank position, to transfer the maximum amount of energy contained in the expanding gasses. This point does not vary much, but the burn time does, and that is why we have to lite the fire early at low rpm, very early, but that timing has to drop out rapidly with rpm and especially with load, and there are other factors such as altitude, inlet air temp, and cooling system temp( actually chamber temperature). And to some degree, the temperature in the exhaust .

If the pressure peak is too soon, then the crank is not rotated over far enough, and the rod-bearings take the hit.
If the pressure is too late, the rod bearings are happy, but the engine loses efficiency; that is too say, the expanding gas energy chases after the piston and does not push on it as hard as it could,if the pressure-peak had occurred a lil earlier.
Your job is not to throw timing at it in the hopes of accidentally lucking into the best place for this to happen.
Your job is to hit as close to it,but not too early, as often as is possible, from stall to ~3600rpm, to maximize your average peak pressure. But especially NOT to HAMMER the rodbearings to death, or break the piston skirts off.
So how do you do this?
Without a dyno, Ima thinking it is next to impossible.
So in the field, you have to sneak up on it. And since you are setting the POWER-TIMING, the best thing to do is to be conservative,so you don't break stuff. Furthermore, you gotta think about how often your engine is gonna be in the zone from stall to 3600 at WOT, and how heavily the engine will be loaded, that it will be missing the very few horsepower, that a slightly too-late ignition timing might cost you.
For example, going back to the previous combo that was 2400@50mph in top gear with a 727. Again assuming a 2400stall TC.
If you were to floor it at a dead stop, the rpm scoots up to 2400 right away, instantly bypassing all the timing below that. At this time, the engine doesn't care about any timing below the stallspeed. At this moment, all it cares about is to have the exact right timing for 2400@WOT; or LESS, not more.
At about 16 mph she will hit 3000rpm, and at 20 mph, she will hit ~3600rpm; where I am suggesting you max the timing at 34*.
So that is the first zone to be concerned about, namely stall to 3600 which is stall to ~20 mph ( remember I geared your can to be at 50MPH@2400@zero-slip. This assumes something like 4.30s and 28" tires.)
So already you have one data point of timing, namely 34* at 3600rpm, and some other number at stall; and I earlier suggested 26* at 2800. So lets figure that one out, and then correct it to 2400.
I'm gonna suggest that your idle timing be 14*, an arbitrary number I know your engine will like.
And I suggest you begin the advancing at 1000rpm, with an idle of no more than 750,in N.
Ok now, from 1000 to 2800 is 1800rpm which will be the working range of your advance, in this case.
And the amount will be 26 less 14=12*
So then; from 1000 to 2800, the advance will climb from 14 to 26, understand that? If that is true and the curve has to be linear, THEN; the rate of advance will be
12* per 1800rpm, which I will restate as .67 per 100rpm. and
Now we can calculate the timing for your engine, anywhere from idle to 3600rpm and beyond, simply be using the .67* per 100rpm.
So, at 2400 your timing will be 2400 less 1000 =1400 rpm, and 1400/100x.67=9.4* which we add to the initial of 14*, to total 23.4; at 3600 it will be 3600 less 1000=2600 rpm and 2600/100x.67=17.4* and add the initial of 14*, is 31.48..how cool is that.
Ok so now you have a built-in cushion of about 2.5 to 4.5 degrees to play with,to get to a theoretical 36* max timing; simply by changing the initial idle timing from 14* to, 14*plus 2.5 to 4.5
With a computer, you can also change the rate of advance to something other than .67* per 100rpm. In your case you can change the start point and end point, and the total number of degrees of change... right?
So you program the start point to 1000 and endpoint to 3600 and the amount to 34 less 14 suggested initial= 20*. Then you set your idle timing to 14* at anything less than 1000 rpm and you are all set.
This is a starter curve, and I think it's a pretty safe curve, so you don't kill your engine on the first trip. It may not make full power anywhere in the rpm band from stall to 3600, and it will, without "vacuum advance", make terrible fuel economy........ but at least it won't blow up.

Now, lets look at second gear.
Geared for 2400@50mph, then 2400rpm in second will be about 25mph at WOT. Will your engine ever be there?
Not if your Kickdown is working; she will downshift into first and shazzam away you motor.
How about at 3600rpm? This will be ~38mph in second, and if she downshifts, then this could go to more than 5500, so NO, the trans will not kickdown. In fact 5000 in first will be about 33 mph. If you are over 33 chances are the trans will not kickdown, so lets start at 33 mph.
In second,now at 33mph, your rpm will be ~2500 at zeroslip,so perhaps at 3200 with a slip-ratio of guessing 30% in the TC. So with my conservative tune, this is 29* timing, which should be safe. To this you can still add 2.5 to 4.5 on the initial, to get you up to 31.5 to 33.5 of Power-Timing; see how nice this is working?
Lets go to third gear. The 2-3 split is .69 compared to the 1-2 at .59 so it will be even better, so I won't bore you with more math.
so in conclusion; the curve I outlined is pretty safe, certainly within a handful of degrees.
What does 5* not enough timing cost you in horsepower, between 2400 and 3600 rpm, which is zero to 20mph?
IDK the answer to that; but I bet not a second of time.
What would 1* of too much timing cost you?
IDK the answer to that either, until the rod-bearings and/or the piston skirts end up in the pan... then I can estimate; a new engine.
So whatever you do, sneak up on it....................