Timing question

[fixkick]

I see one maker of ECU (after market)
that is called the NO fuel ECU, or spark only ECU.
its just that, a black box, you tune, to get spark timing perfect. (+ map + ckp sensor and TPS)
exactly like the 3d curves above post. here it is , shows you the complexity.

"ignition only ECU."
his page 14 map is just default map, and useless (well it runs), for any engine, it must be tuned to what your engine needs and your carb AFR. (dyno time is expensive.)
I do know a guy that uses a home made accelerator. (crude HP gage really) and tunes spark at all loads, and RPM form max accel.
one can do , 3 points on a line and then interpolate , them for a base line, and then do more. for more accuracy.
I have a program for my mega-squirt ECu that measures, RPM accelerations ! Rates , rates fast are more HP, and I tune for that, offroad, away for cars and trees.....
its DIY program that turns the car in to a DYNO, but with due care, , 2 persons is best, one to drive , one to tune.

http://www.canems.co.uk/pdf/ignition_manual.pdf

PS
im sure this is no direct useful solution to your problem ($$$$$)
but learning how spark really works, is a solution, or can save you from trying the impossible..? (seems this is the case to me)

the real problem is there is no full Suzuki spec on this distributor at all (the rpm curve and the Vacuum curves are missing)
that means you cant' make something work close,
the rock and a hard place.
this is.

all the best there in SA>.. good luck to you and your countymen...