6L80 shift point issues

[bdubb]

I have recently noticed a few shift point issues with my original tune when rolling into the throttle. When it used to shift at 6,000 rpm it was starting to hit the rev limiter at 6500rpm.

I have now gone with a gear change from 3.42's to 3.73's and tried to get some tuning in based on bluecats spreadsheet. However, despite my various efforts I am seeing shifts occur as much as 1200rpm above my set points for rpm and mph. I am VERY new to using HPTuners and am trying to learn so I don't know if I am doing something wrong with the tune or if this is a sign of a convertor (stock) or trans issue.

The original tune was performed by tuner from a well known performance shop in the Houston area and as it was never an issue until recently I am thinking it may be mechanical in nature.

If anyone wouldn't mind reviewing a few tune and log files to comment on if I made any errors I will post them up. Even trying shift points (rpm & mph) in all tables as low as 5000rpm had me actually getting the shift around 6200rpm.

Vehicle is a 2008 Sierra Denali. 6.2L L92 with AWD and 6L80 along with a whipple at 8 to 9 PSI and a few other items.


Any help would be appreciated.

[TimC]

Sure, post the tune. The RPM has little to now affect on the actual shift point depending on who you talk to. I agree that your problem might be mechanical. Do the shifts seem to take too long and do the RPMs flare during shifts?

[bdubb]

They have flared in the past, but these shifts (for the most part) feel fine just way over the intended shift point.

Driving around town the part throttle shifts are fine for me but the WOT is another story as I don't have much faith in the room for error when hitting 6500rpm under boost and with stock L92 valve train.

[Shrek]

... I don't have much faith in the room for error when hitting 6500rpm under boost and with stock L92 valve train ...

You invested a significant amount of money in a supercharger, but didn't upgrade the pushrods and valve springs as part of the project ?

[bdubb]

Here is one of the runs, some of the other logs I took appear to not want to open at the moment. At this point I was just trying to adjust the shifts down low enough to allow a complete pass without hitting the limiter, which still did not happen regardless of the very low shift point settings.