With the carbs,
I would run initial to get total where I wanted it if not recurving. However, if I was building the distributor, I would want initial higher, like 16-18 to start. The old cam needed that more initial than this one, but the big intake and low RPM cruise in OD will want all the initial it can handle.
Your throttle blade challenge is not over with the carbs either, you need to make sure both sets of primaries (and best if all) are not dipping into the transition circuits.
If you are running a vacuum advance later, you have two options. You could run 16 initial, 36-38 total and then add ported vacuum to the can. Or you could in your case, run manifold vacuum. I don't love doing that, but in your setup it could add to the high vacuum mileage and drivability when in OD. It'd be worth a try. initial and total stay the same in that case, but you would likely have to lower the idle equally on both carbs compared to with the vacuum from a ported source
Be sure your new gear is at the correct height on any distributor, nothing worse than fragging a motor because a roll pin or gear breaks...
With the EFI Same goal, more initial timing, equal blade location and as much timing as you can get to it on part throttle cruise
The timing should be set before you do your final throttle adjustments and IAB setup. Consider the timing as a mechanical function, even though it is adjustable. Initial and total are hard numbers, then you can tweak how fast it comes in after. With EFI, I would want the crank timing a little lower, maybe 10-12, and then as soon as it fires, idle should be around 20-22. Additionally , if you look in your instructions, there are a ton of adjustments at different "KPA", these are adjustments for timing at different load based on vacuum. When vacuum is high, you want more advance, the key focus is your 50-75 mph light throttle cruise.
But then, and what I think is most critical, after the timing limits are set, I would, in absolute detail, learn how the throttle blade, IAB and TPS relearn function works and set them up the way the computer expects them to be set up. I agree with Barry that two IABs are goofy if that is how it works, IMO, unless there is a reason one cannot open enough or fast enough, which I doubt the issue is. Regardless if that is how the program works, so be it.
In the end, the throttle blades primary and secondary should be matched, and set so that it takes a certain amount of IAB to idle. Usually, with the IAB unplugged, the engine barely idles, then the IAB adds a little air to get it to the idle speed you want. This allows it to compensate for things like A/C, PS, etc without being too far open. Remember, any time you adjust a throttle blade, you have to relearn TPS or it thinks you have your foot on the pedal. My opinion for later, not having read the setup for yours is.
1 - Adjust blades to match each other without being fully closed
2 - Fire engine, go through setup, to include TPS limits, initial and total timing, and air fuel goals,
3 - Check IAB values
4 - If required, adjust both throttle blades equally (don't screw with initial timing anymore)
5 - Reset TPS values
6 - Check IAB values
7 - Repeat if necessary from step three until you have the proper IAB
8 - Once idle setting is where you want it, start playing with load-adjusted timing (KpA in your instructions)
