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I have a question about lean cruise on a VR V8. The map shows a figure that is as high as 3. I understand that this number is added to the already 14.7 making it 17.7:1? This can't be right considering that about 15.8:1 will achieve minimum fuel consumption. I am thinking of changing it to about 1 and making cover a bigger RPM and load range. What are the thoughts on this?

theres no perfect answer, other than every motor is different .....

as long as you can't feel it engage then its probably not too lean, but as for the right number and what area to populate would depend on the engines gearing and what rpms you normally cruise at.

Mid 15s nets the best economy, but exactly where you will need to experiment. The factory setup I feel is too lean, normally I target 15.4-15.8 during lean cruise.

That's around where I thought it should be. I think the factory setting is too lean also. The power loss would cause it to drop out of that part of the map to easily and not really achieve the desired result. Ill work on 15.4 to 15.8 over a wider range and try it.