I have a Holley 6280 carb and I keep hearing the term "lean burn". What is it and how do I know if I have it? From what I understand it is a small computer located on the air cleaner housing.
My van is a 1985 B250. Engine is 318.

 

Welcome.

https://www.allpar.com/mopar/lean-burn.html

 

Thanks for the info. I do not see the "Black Box" on my air filter housing, but my Full Service Manual makes several reference to the Spark Control Computer, which I think is the Lean Burn System. I don't see any kind of computer or box anywhere. From what I read online there was an option to remove it, so I assume I either don't have it or it was removed. However I have a 1985 B250 van, and sometimes things are mounted in strange places, so it could be mounted somewhere else.

 

While the Lean-burn system was in full swing in 1985, there's a good chance your van didn't have it. The computer was mounted on the air cleaner. It depended on the GVWR wether it qualified for that pollution control system. I had a 1985 Dodge 150 pickup, which was rated as a "heavy-half", and it did not have lean burn.