They don't have any o2 sensors that react fast enough? I know Giles (Holyroller Dyno) was able to use the Innovative wideband coupled with the Emanage Ultimate for closed-loop o2 feedback. The green immobilizer key light would indicate when you are hitting an ideal AFR. I remember even in first/second gears, the green key would illuminate relatively quickly. Maybe not quick enough for FI, only NA?

 

You would still tune the fuel maps to get close to the target value. The fine tuning would be part of the closed loop operation.

 

If you want to see how quickly your O2 responds, move 2 fuel indexes very close to each other (ie. 3500 and 3501), and increase fuel of the first by a couple percent and decrese the fuel of the second by a couple percent. Then look at how sharp the transition appears in the datalog for each gear. I suspect that it will look like a cliff in 3rd gear, but a tiny wave in 1st. I also suspect that the wave will appear a few hundred RPMs higher in the RPM range than it does in 3rd gear.

Note: I haven't actually tried this, but that is what I think will happen.

 

I don't think the issue would really be that the STFT would be a bit too big or a bit too small. I think that it might be a few hundred RPMs too late. Basically, by the time the ECU decides that the STFT needs to be +2%, the RPMs might have already climbed to a point where STFT really needs to be -2%.

 

During wot, the ecu is in open loop. During closed loop operation (part throttle), the ecu adjusts for 14.7. With k-pro for example, you can disabled closed loop and tune part throttle to be leaner to safe more fuel and leave closed loop off. I tune part throttle to 15.5 af and wot for n/a at 12.8 af. Boost between 11.5-11.8 af