If you want to find out what curve the engine wants (they ALL want a curve and that curve is almost never all in by 2500 as Jenkins proved back in the 1970’s and for that particular combustion chamber/rod to stroke ratio/compression ratio/gearing/chassis etc that curve is still the same) you need to load the engine at different throttle openings and RPM, let the engine stabilize and then move the timing until you find peak torque. You write that down and move to the next throttle opening/load/RPM and do the same.
Once that’s done you have to put the distributor on the test bench and make it match what you found while testing.
I think many people would be surprised at how much timing an engine will want above and below peak torque and that most engines want LESS timing at peak torque than it does at peak power.
You can spend a TON of time sorting it out.