I have been searching here and asking around and still have a question about the ALDA. This is in reference to my 91 300D 2.5. Some say that adjusting the ALDA only effects off idle fuel and others say it effects fuel delivery even after boost comes up. I have turned my ALDA up about 3/4 turn and can tell a difference off idle and it seems after boost. However it makes boost come up sooner which may be why it feels like it runs better overall. It still doesn't smoke so would it be safe to adjust it some more without effecting effeciency?
Some things I have done to the engine if anyone is intrested.
Car has 298500 miles on it and uses no oil between changes.
All three of the vacuum valves (or what ever you call them) over at the air cleaner were bad when I got the car. Valves bad = no boost.
I bypassed the boost valve but then boost went past 20 psi so I had to have a way to regulate it. First I used another overboost sol to remove vacuum to the wastegate but that caused the boost to go wildly up and down. So I removed the EGR valve, cut a plate the same size from 1/4 in steel. Used 2 bolts of the correct size, put 2 compression springs on the bolts and then used them to hold the plate on the EGR port. Invision a steel plate held against the intake by two springs. If the boost goes to high it will compress the springs and let the plate move away from the EGR port and lower the boost. In other words I made a mechanical waste gate. It is set at 15 psi.
This also does away with the EGR which keeps the intake runners cleaner.

This car is my daily driver which I only paid $1000 for. I can put the car back stock at any time for about another $1000 in parts by I plan to drive it until it falls apart so if it works now why change it.

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84 500 SEL (307,xxx miles)