Toyota 2.8D idle speed

Idle speed, is 750, or Just set your needle's top level with the 750 mark on the tacho.
For idle up with aircon, 950 will give you the least vibration, and its what the factory setting is.
I personally just had it set so that it stayed at 750 when the ac compressor cycled on.

Up to you.

Trains

I had myn set at just under 700 and 900 with air on. If there is not enough revs when aircon compressor is engaged on an extremely hot day when say sitting at lights the condensor will not work as efectively as it should as the clutch fan wont pull enough air through quick enough to keep it and the radiator cool. This is more when sitting in stop go traffic. The only downfall is when in low range going down some thing very steep you are best to turn the air off other wise when the compressor kicks in it will idle up causing the vehicle to speed up down the hill. Regards Steve M