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      12-04-2011, 12:57 PM   #79
MFGJR
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Drives: 2007 Z4 M Coupe
Join Date: Sep 2008
Location: Richmond, VA

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Quote:
Originally Posted by MFGJR View Post
Here's an example--the blue lap is from run 14, the others are from runs 4, 7 and 10 and their speed traces all make sense vs. the track map. On the blue lap, you can see what's obviously the 130+ peak speed on the back straight showing up--erroneously-- at turn 11...
The plot thickens (can you tell I had another insomnia night?):

It appears that only the Solo-sourced channels are whack--the ECU-sourced channels look fine. In the speed-distance graphs blow, comparing run 10, lap 10 (green) and run 14, lap 3 (blue), the upper pair of lines are from the Solo, while the lower pair's speed data are coming from the ECU. You can see the stagger bewteen laps in the upper set, while the lower laps synch up perfectly. The two green lines look identical, while the profiles of the blue lines differ significantly--see the slope difference between the two blue lines coming up the back straight (indicated by the red line connecting the two).

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Here's another example, the upper set comparing ECU-sourced brake pressure between the two laps, and comparing Solo-sourced lateral accel on the lower pair. Again, the traces synch for the ECU-sourced brake pressure, but the lateral accel is out of synch.

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Bad news, we don't understand what's going on here. What's wierd is that even with the ECU-sourced data, it seems that the Solo has to index the data to a distance, which has to be coming from the GPS. So, my theory that the start-finish beacon was reset may not be the answer. If that was the case, it seems that all channels would be off.

Good news, at least Randy has reliable speed info to compare his best laps that were in run 14--just needs to use the ECU spped channel instead of the GPS speed channel.
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