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Chalky
June 4th, 2008, 04:53 AM
When I dyno and use the operators WB and use my WB, there tends to be a discrepancy in my logged AFR vs the operators WB AFR readings. I tend to trust the dyno operator's WB more than mine on a short sample such as a dyno pull. This also made me wonder why we see the discrepancy in values. Is it because I am tracking to many pids, (23 max) or is it an inherent issue with the data logging process of a store bought WB02?

When I do auto VE, my pid count is usually maxed @ say 23 total pids selected. AT this point, I end up trying to gain as many cell hits as possible to get a reliable VE MAP. Up wards of 25 to as many as 50 and I start to get comfortable with the data value.

If I reduce the number of selected PIDs to a minimum required to log AFR only, would the number of cells counts increase with fewer pids selected?

I don't mind doing the lower rpm cells when doing my BEN MAP but the higher rpm cells is asking for trouble. I live in the flat lands of the Midwest.

Bottom line, short question, is the a better way to improve the reliability of AFR readings with a shorter driving period and fewer pulls to max RPM?

jfpilla
June 4th, 2008, 05:29 AM
It could be what you say or where the operator places his sensor. I had an extra bung put in the opposite header and the discrepencies are now minimal. In any case, note his AFR when getting max power and set yours accordingly.

joecar
June 5th, 2008, 02:35 AM
Have a read of Appendix E in the scantool user manual pdf, I think that may explain the pid logging speeds.

Chalky
June 5th, 2008, 03:22 AM
Have a read of Appendix E in the scantool user manual pdf, I think that may explain the pid logging speeds.


Thanks.