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To all considering a Megasquirt D-jet setup, get an adjustable fuel pressure regulator instead of a Datsun piece like many of the websites suggest. I just got mine yesterday (a NOS brand universal unit with the vacuum compensation port can be adjusted from 0-60 psi), and it seems to make a huge difference in tuning. I dialed my fuel pressure to 25 psi with the engine off (used a pressure gauge) and told megasquirt to use 4 squirts per engine cycle alternating the injector banks instead of 2 squirts alternating. My idle pulse width went from 1.7ms to 1.55ms which is pretty low but not bad for twice as many squirts. The driveability is much improved and my acceleration problems seem to be less severe even with all acceleration enrichments turned off. I still get a pretty fat lean spike during acceleration but the air to fuel ratio doesn't swing as wildly afterwards, and the car only gives a slight buck. Way better than what it felt like before changing the fuel pressure. Once the general tune has been established I can dial in the acceleration enrichments.
I don't know why the stock d-jet injectors are so huge, but it might worth looking for smaller injectors if you don't have good ones yet. With smaller injectors you could even run 4 squirts per cycle simultaneous (both banks of injectors squirting at once), this is supposed to be as close to sequential FI as you can get as the fuel is more evenly distributed among the cylinders at all times.
Also another thing that I have learned is that the engine runs better with the injectors wired differently than stock. I have the two banks wired 1 & 4, and 2 & 3, instead of the stock: 1 & 3, and 2 & 4. Not sure why it's better but that is the conventional wisdom among the DIY injection crowd.
Hope this helps folks collecting parts for the conversion,
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