edoad

What Bins pertain to fuel air mixture in the 85 EPROM?

rons85

You are going to have to explain the question a bit. A "bin" is a BINary file. Something stored on and downloaded from a Prom chip and a file which can be edited using a binary file editor (like Tunercat or Tunerpro).

Do you mean which data Tables in the .bin file for an '85 control the air/fuel ratio?

If so, well - none of them, at least not in closed loop. The target Air/Fuel ratio is Fixed (and not available for edit, although you can probably find a way to "hack" into the .bin file itself to change it if you think in hexadecimal - another thing altogether...) at 12.7:1 in closed loop. It can be changed in Open loop and also in WOT mode, but not in normal closed loop operation.

Rohn

There is a commanded A/F that can be changed for closed loop(stoich). many do so to accomodate ethanol blend fuel. some just want a richer CL A/F as are non emishions. mine is set to 14.3/1(10% ethanol) and my NB02 swing points were increased in .bin as well.

rons85

Not in '85, at least not in any $1F mask I've seen.

mseven

Not sure what ecm you are refering to,
If using a 165 or 727/730, when looking in the tables/scalers and then changing the number in the "stoichiometic air fuel ratio" will not change AFR in c.l.
The upper and lower R/L threshold tables can be used to move the basic AFR. As they form the O2 Error Window, by raising the table values toward the richer side, the overall engine AFR can be pushed toward the rich side (lowered AFR). These three tables define the overall AFR when in closed loop. The proportional term is always trying to move the current O2 sensor toward these table boundries.

Rohn

My error. I was refering to my 8746. I thought his ECU was similar.

Quote: The upper and lower R/L threshold tables can be used to move the basic AFR.

that is what I was refering to. In the 7747 and the 8746 it also has a constant for stoich A/F.