has anyone logged 6l80e pressures

[icicleboy]

I did. What I found was that even though my max line pressures are up around 175, and my 1-2 shift pressure on the x pattern (all patterns set to x) is set to 200psi at 403 ft/lbs not one of the pcs sensors I'm reading exceed 109 psi. Has anyone else seen this issue? is it a pid issue, or possibly something else?

[camaro1]

yes i found that same issue, all the pcs readings max out at 109.9, i wonder if it is just the scanner table maxed out, or if the pressure changes really dont do anything??

[icicleboy]

I tried bumping the master maximum from 275 to 300 but didn't see any change at all. I am now wondering if there is a hard coded maximum somewhere that is holding us back.

What is interesting is that in all my trans tuning so far.... I notice a big difference at part throttle shifts where line pressure used to be lower than 109 (but now is). But at wot, where it was already 109, and still shows 109, I don't feel any great difference. This leads me to think that we aren't going past 109.9 at all. I hope Chris can chime in here.

[04blackgmc]

ive logged it many times and its what i get also

[icicleboy]

this would also explain why there are lots of guys out there with shift issues over 500whp.... they keep raising shift pressures but they might not be actually going up past the 109.9...... very curious to see what Chris@HPT might say as I've asked him to chime in here.

[carneb]

It's because the pressure is being reported in a different way in the scanner. If you look at this thread http://www.hptuners.com/forum/showthread.php?t=18561 post #10 it explains it. The base pressure tables and Max Pressure in the editor gives the pressures as line pressure, the Max line pressure table and the pressures reported by the scanner gives the pressures as PCA pressure. Hopefully the link I've included will help to explain it.

[icicleboy]

I still don't get it. I see a max of 109. If that is PCA (or CPA or something) it still should have gone up when I inreased my master line pressure from 275 to 300.

109 * 2.045 = 222ish psi, and I'm hitting that at much lower delivered torque then I should be based on the table structure as well......?

edit : how can all different users be hitting a max of 109 when we all have different max pressure, gear pressures, and shift pressures? :S

[camaro1]

looks like i might have to manually check the pressure with a gauge, the line pressure tap port is on the pass side near the bell housing,, im doing an oil change on my car today so ill see if i can access the port without too much trouble,

found this in the gm service manual for doing a line pressure test on the 6l80e and commanding the state of the pc solenoid:


Scan tool Line PC Solenoid Commanded State vs actuall psi

None 45-80psi
200 95-130psi
400 160-190psi
600 220-250psi
800 270-300psi
1000 270-300psi
1200 270-300psi
1400 270-300psi
1600 270-300psi
1800 270-300psi
2000 270-300psi

[Chris@HPTuners]

i think have found the issue, there are two limits *sigh*

One for "line" pressure and the current limit shown in the editor. I will add the other one and see if it fixes the issue.

Chris...

[camaro1]

sent my info to you for when the new version is ready to try

thanks

[Dan Wendling]

Please PM or email me when a beta with this fix is available. Let me know if you need my ID so you can post the beta to be visible on my account.

Thanks

[icicleboy]

i think have found the issue, there are two limits *sigh*

One for "line" pressure and the current limit shown in the editor. I will add the other one and see if it fixes the issue.

Chris...

Chris,

any update on if this has been added to a beta? I'm not pushing on my truck until I know this is solved......

[vhato]

I am so glad I came here today.

I have been tweaking Part Throttle Shifts and Pressures for two days. And even reprogrammed a few times with no results. I am currently running 2.23.3377.39362. Is a newer version available?

Would be nice because I forgot this version sometimes corrupts the .HPT file causing me to re-read the ECM/TCM which bricks the TCM from further writes and forces it into some weird protect mode. I did it a gas station parking lot. PITA trying to pull the positive connector to reset the TCM.

[Mike@ADS]

I'd love to have this beta as well when it is ready. Should we just e-mail support for the newest beta? If so, let us know when it is ready.

[camaro1]

any news?

[Chris@HPTuners]

i added two new parameters, they should be in the next beta which Keith tells me will be this Friday.

I found another max pressure limit for the main pressure control solenoid and also a max clutch pressure, which seems to limit pressure for all the other clutches (i'm not sure does anything it seems pretty high already).

Some of these may appear to be calibrated after the regulator gain (hence be roughly 2x what you expect).

Chris...

[04blackgmc]

good to hear

[Dan Wendling]

Is this beta release available yet?

[icicleboy]

Is this beta release available yet?

ditto. Waiting for the email.

[Bill@HPTuners]

Not ready yet guys, likely sometime next week I was told last night.