a/f ratio

[mattmor]

Has anyone ever experimented with Closed Loop A/F Ratio values in the chip $342A . Factory is set to 6Fh - 14.76. This is the commanded a/f ratio and the computer tries to maintain it correct? Would it be a possible gain by tweaking this value? Any help would be great as I am still very new to chip programming.

Thanks

Matt Morrison

 

[TurboJim]

Not much to gain. Maybe a little idle stability. The thing is you must change the O2 correction window as well, and our O2 sensors arent very accurate outside of stioch.

 

[TurboTR]

Carl Ijames did some extensive experimenting with this a year or two ago and appears to have achieved good results from an emissions testing standpoint. He also did a nice writeup on it, I think to the gnttype list if I recall.

TurboTR

 

[ijames]

See my other reply under fape for more details. Basically if you just change this constant, the blm's will learn to new values and the actual air-fuel-ratio won't have changed. That's because the actual afr is set by the O2 sensor parameters and not this number. This number is just there to make the units reasonable for everything else in the fueling equation.