In my case, I used my dialback timing light to work out the curve from the Pulsar dizzy I had in, then put that map into the black box.
I've massaged the curve a bit since, but it was close to being correct.
My curves are shown in the Stealth box thread.
[edit] Here's my current map, note I add 10deg all to these points (by setting dizzy @ 10degBTDC, not at TDC) because of my race head's bathtubbed chamber shape.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.
