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Sorry to stir up so much dust... but doing a little thread digging

Doing some tuning on a couple of 4L60-E's and came up with a curious observation.

Comparison below is between the corresponding tables of an XU6 tune (DDRJ2641.bin / $A5K.xdf) & a VY tune (9261296.bin / $060A.xdf)



Im guessing that the values in the HSV tune are only part of the story and may be a percentage or multiplier of a base value elsewhere - missing scalar??
I cant imagine the box would even work with so little pressure.

Soooo,
That said, what sort of advice would you give re increasing shift pressures to improve shift speed/quality.
I am tempted to apply a +5% across the whole table as a starter... but if anyone has any advice that would be appreciated.

Cheers, Chris

I'd say the second table as you say is not scaled right or something, because I know most tunes have nothing over 90 psi in them, and i'll also advise against applying too much pressure in the first few cells (ie. 0 tps or 0-6kms)

you will find if you do this and say reverse out of your driveway, while still rolling maybe only 1-2kms backwards if you put it into drive with too much pressure there it will bang in pretty hard.

like oyu say try small amounts at a time and see what change you get ...

you can see from the table at 87% throttle your getting all the box has got to give, its more about getting the other areas more crisp .... but its easy to go too far

also keep in mind there are some tables specific to each gear as well for shift points and adding pressure for that gear only etc.

Are you using the latest .xdf from HERE VY V6_$060A v2.63.xdf
Conversion from hex to psi is straight 1:1

Hi gents, thanks for the quick replies

Holden202T wrote:I'd say the second table as you say is not scaled right or something, because I know most tunes have nothing over 90 psi in them, and i'll also advise against applying too much pressure in the first few cells (ie. 0 tps or 0-6kms)

Thanks mate - i'll keep that in mind... my new daily has a 4L60-E and now that my 6L80-E (weekend/track toy) shifts perfectly i'll see if I can apply some of what I have learned to this old girl

darcy wrote:Are you using the latest .xdf from HERE VY V6_$060A v2.63.xdf
Conversion from hex to psi is straight 1:1

Cheers darcy, I'll try opening the bin with that xdf... I was actually using the xdf from MemcalIDTool (14/1/2012 build)... xdf appears to be v2.2
Fairly obvious solution and one I probably should have checked
Many thanks for the heads-up

Have a great weekend guys

* Update.

Yep the v2.63 xdf scaled the pressure table correctly - much more sensible numbers now!!!

Thanks again darcy