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here is the O2 data from my runs.
1st run, 2nd gear run, safc set to 0 across the board. 3000 to 4000 rpms 0.96V. From 4000-4700 rpms it was a bit leaner, around 0.94V with the largest dip being 0.92V at 4300 rpms. Then from 4700 rpms up we're talking 0.98V (real rich) so it did, at stock settings, drop a bit at 4300 rpms, but it was a very shallow dip in the
2nd run; 2nd gear pull; safc: 3k rpms 0, 4k -5, 5k -7, 6k and up -9
2500-3800 rpms O2 went from 0.96V to 0.88V. Between 3800-4700 rpms it leans to 0.62V. From 5100 to 6000 rpms O2 was about 0.90V. From 6000 rpms up to redline O2 was 0.94V. Timing was at 20 degrees, dropped to 17 degrees at 4800 rpms then increased to 23 degrees at 6000 and stayed there to redline. This run, the O2 voltage leaned out.
3rd run; 2nd gear pull; same safc settings, the O2 voltage and timing curve was the same. It was running leaner between 3800-4800 rpms, but the O2 only leaned to 0.81V at 4300. Then I shifted to 3rd gear. The O2 voltage held rather steady at 0.88V between 4800 to 6000 rpms in 3rd gear. In 2nd at about 4300 rpms again, it leaned out, but not as badly. In 3rd gear I think I've got the tuning right. O2 voltage is at 0.88V in the rpm range the car runs at the 2nd half of the 1/4 mile, which is about 12.7 to 1, right where you want it for power on pump gas.
4th run; 3rd gear pull from low rpms; safc: 2K -3, 3K -4, 4K -4, 4.5K -2, 5K -7, 6K and up -10. I richened it up a bit at 4.5K rpms to compensate the leaning out. From 2300 rpms to 3000 rpms O2 were about 0.98V, 3000-4000 rpms O2 were about 0.94V to 0.96V, 4000-4400 rpms O2 was about 0.90V, 4400-5100 rpms about 0.94V. I shut it down before I got to the 5-6K range in the previous run. Again, a slight leaning out in the same range, but not as noticeable.
5th run and 6th run; 2nd gear pull, same safc settings. O2 was steady from 3000-6900 rpms around 0.92V or so, but leaned to 0.69V at 4300 rpms again. The voltage drop was from 3900 to4600 rpms.
7th run, same safc settings, 2nd gear then 3rd gear pull. O2 voltage was the same in 2nd gear except at 4200 rpms it only leaned down to 0.81V. From 4700-5300 rpms in 3rd the O2 stayed at about 0.88V again.
8th run, 2nd gear pull, safc setting the same EXCEPT I put the setting at 4500 rpms at 0. The O2 voltage was steady again, and only dropped to 0.82V at 4200 rpms, with almost no drop in O2 voltage before and after 4200 rpms. It was a much smoother O2 graph than the previous runs.
OK, lots of data here! This is what I make of it.
No SAFC settings, in 2nd gear, there's a "slightly leaner spot" in the fuel map. Why??? Best guess, this is where the torque drops off in the mid range (like most non vtec DOHC cars) and they lean it a bit from the factory to bump up the power where the torque drops off here.
In 3rd gear, the tuning is about right from 5-6K rpms. Keeping the safc setting higher at 4.5K seems to help around the "lean spot" in 3rd.
In 2nd, keeping the safc setting higher at 4.5K seems to help the lean spot too. But for some reason when the safc is set leaner, even if it's just around this rpm point, the O2 voltage seems to drop more that if there is no safc setting. I have no idea why.
I'm going to try more baseline runs, and I'm going to try comparing those to leaning it only ABOVE 4500 rpms. Example, 4000 rpms 0, 4500 rpms 0, 5000 rpms -7, ect... I'd like to see if the O2 drops alot if the safc is set to 0 at and before 4500 rpms.
Realistically, this setting is all I'll need since except for the launch you don't see less than 5K rpms in 2nd or 3rd at the drag strip, and the launch in 1st happens so fast, who cares if it runs lean. But, I think this should be figured out.
"Tutto fa brodo."
Todd Scungio
98 RS
15.173 @ 90.70 MPH
And also a 2011 Ralliart
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