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Please help! Can anyone see why it's shifting early?

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Old 09-22-2014, 10:52 AM
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Default Please help! Can anyone see why it's shifting early?

As you can see in the log the car shifts at 6422 @ 44 mph. I have the MPH tables zero'd out at wot. It should shift at 6800 as commanded. I'm going to log the commanded gear next time but I dont understand why it's shifting early? Also when it shifts it's either going straight to the next gear or it's locking up the converter. To me it feels like it's locking up the converter. Which you can see by the bump in RPM after the shift followed by a dramatic drop in RPM. This also makes it take forever to recover making for a very slow run.

I've attached a copy of the log and the tune. Can anyone see a reason why it's doing this?
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File Type: hpl
md2ndfull.hpl (35.6 KB, 64 views)
File Type: hpt
Chuckstunelast.hpt (462.6 KB, 60 views)
Old 10-02-2014, 08:49 PM
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for one...log less items and add in some transmission parameters...
add in trans current gear, trans shift mode, and time of last shift for all gears
likely you are just seeing long shifts because of long desired shift times

also, it will never shift at the exact rpm you command...it will always finish at a higher rpm than commanded...
the commanded rpm is just where it commands to start the shift (henceforth the need to zero out the desired shift times)

in your tune zero out the desired shift time table
and you need to have a mph in the full throttle shift speed for the downshifts... 2-1, 3-2, 4-3
otherwise it can get stuck in gear and not downshift at all, or it can shift into the wrong gear at WOT because it doesnt know where to downshift to.

the upshifts can remain at zero



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