ALDA is only on turbo on engines, you have an ADA. Turning it "up", try it but not likely to make much differance.

Injectors, your stock ones flow very well. Even with a turbo and tuned up ip(injection pump) the injectors are still very good. If your injectors are worn, then putting new nozzles on will make it run better.

Basically do the basics, after that then you need to learn enough, or take it to someone who can help to set the ip a bit higher. Need to be careful about this as you can get really high egt's if you go to much, but a reasonable approach will give nice improvement in drivability. This is really the first step after making sure all else is in order.

I reamed out the pc burn holes too, this helped a lot after ip adjustments. This needs to be done rather carefully so as not to change the angle of the hole.

After these it starts to get a bit harder, make a new intake manifold, or add turbo.

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1977 240D turbo