Technically, this ignition is designed to be used with a locked-out distributor, and a MAP Sensor for vacuum advance (instructions suggest the MAP Sensor PN 23111 for N/A engines).
This means :
- you should determine optimal initial advance setting
using this method for example.
- you should lock the timing on the distributor (how depends on your distributor type).
- you should decide where on the RPM curve you want the total advance all-in. If that was a drag car, I'd say a few hundred RPMS after your convertor stall speed, but for a street converter, that would be too low. Somewhere around 3000 RPM would be a good start. Max advance for a BB is usually 38°.
- Now you have the initial timing value, and the final "mechanical" advance RPM level, you can set a straight curve for a start.
I see no reason for further tweaking for your current engine, you may need that for the next mill.
You could change the end of the curve so that there's an advance decrease in the high RPM zone, but the rev limiter takes care of that.
You may change the start of the curve for easier starts (like having almost no advance at 0 RPM and ramping up to whatever the initial timing is around 700 RPM but your 400 will likely not need much in that area)
You don't absolutely need the MAP sensor for a start, but it's useful if you car sees some road miles.
The original Mopar documentation for the electronic ignition conversion says total ignition advance can be up to 56° for a BB, that's around 18° of vacuum advance, so you'd want something like that at the maximum vacuum your engine pulls when cruising (you'll need to know how much vacuum your engine pulls cruising at 3000 RPM, get a vacuum gauge with a long tube so you can take it for a ride).
If you use the 6530 and a distributor with a functional mechanical advance, the programmed curve should be flat, since the box won't be managing the advance curve. Using a "normal" advance curve with a non-locked-out dist will produce detonation!!
I don't know if you can lock the dist for mechanical advance and retain the vacuum advance (this would be easier than installing the MAP sensor).
