Nobody can give you a PSI for every shift. The PCM calculates the pressure needed at that particular speed, torque, pedal position, temperature, and a few other items. Every shift is different, there is no magic PSI number.

 

Well crap.....so it pretty much comes down to sending a message to the tuner and having them ramp it up or down depending on how it drives until its right?

 

Yes, that's right.

 

Thanks Jason and mark for the explanation, that definitely gives me a better understanding

 

Ugly Pitbull, every truck is different so take this with a grain of salt but when I could barely feel my truck shift my tuner had to raise the pressures way up , one of the tuners I was dealing with told me we we're about maxed out on shift pressures. Unfortunately I do not know the PSI they were shooting for but maybe you can tell GH that you need to go halfway between where you're at now and maxed out If your shifts are really soft. This will give you a good starting point as to whether you need to go up or down from there. If it ends up being too firm you could always revert back to your old tune until you get another revision.

 

HMMMMM, why does anyone want to increase the firmness of the shift? All that does, IMO, is to add shock waves to the drivetrain while pulling a heavy load which is very damaging to the weakest link whatever that may be. Seems to me that it's better to have a nice, smooth shift, then give the pressure to the lockup to hold everything in place, to most efficiently transfer power to the wheels.

 

The best way is to have the right pressure for the shift.

A shift that is too smooth slips the friction material for too long. That will wear it out prematurely. A shift that is too harsh will cause shock loading in the drivetrain and can break parts. There is a happy medium between those two.

 

My new shift lever should be here tomorrow....I did not have the OD function working on that one. Light was off and it would not shift down from OD. I plan to test it out a bit more, maybe get some graphs from Forscan too. I will work with GH on the shifting after I fix this part and do another test drive. It was such a night/day difference from stock with PHP tunes for mod valve body, and the GH tunes w 160/30's .....that I was wondering if it was something else.

Looking for firm....but not jolting. I had a quick, firm shift on my last truck and when I was pulling a load, it was actually quick but smooth. Right now I cant feel the shift....only hear it in the RPM's

^This is exactly what I am looking for.....I have had it before, so I'll know exactly when I will have it again.

 

I didn’t like the PHP “modified VB” tunes. They were too soft with my Tugger kit. The mod VB tunes remove some firmness (line pressure drop I presume) because they are expecting it to be mechanically increased by said modification of the VB.

Something seems strange if you were happy with PHP Mod VB but feel the new GH tunes are too soft.

Maybe try the canned PHP tune you used to like just to see if there’s a difference? They say the single shots will run on split tunes but will be kinda quick on the pedal. Of course using less pedal may cause the shifts to be softer in that tune too now.

Have you considered just putting the Tugger VB back in it?

 

I sent the Tugger VB in to Clay as a core.
I am going to get the new shift lever back in tomorrow and take it for another spin and pay closer attention to the shifts. I just recall really having to slam the pedal to get it to downshift....but that could have been the lever too. Ruling it out I guess. (no OD light...and it would not shift down when the button was pushed)
I recall this truck shifted very soft before....regardless of whether I used modified VB tunes or not. My old 2001 was the dream shifter. I still get sick about selling it when I see it on the road......my buddy bought it from me.
I plan to follow up with GH on Wednesday after this 2nd test drive.
I might try downloading one of the split shot tunes just to test. I did send an email to PHP to inquire as to what tunes they had in the Titan Unlock for 160/30's with a modified VB. I can find the stock tunes everywhere, but nothing for upgraded injector sizes.

 

I don’t think you will want to run the modified VB tunes. They will shift softer than the normal ones.

There are a couple guys around here who have screenshots of the Titan unlock. Not too many file choices available from what I’ve been told. Well not like the selection you have on the free library anyhow.

 

My plan was to run the modified in order to let the valve body do its thing.....but if it isnt working properly, I will have to rely on the tuning to up the pressure.

I got this email from PHP this morning...... "You will have almost the exact same set of files available for stock, just re-written for the injectors. It will be a full complement of files. You will have standard transmission files and “Modified Valve Body” files. If you have a race or “built” transmission, your transmission may fall outside of those two sets of tunes."

 

@ESwift can you share a screenshot of the 160/30 Titan file choices for box code VDH2?

 

I have yet to see modified vb tunes for many Titan unlock options

here are what is available




They do have some 180/30 with a hybrid shift strategy, not sure what all that is lol

 

Thanks for that.....

That was exactly what I wanted to see, thank you!
They do have quite a few for my box code, but you are right...no modified VB tunes. I might just have to pull the plug on these if GH cant get it right. I supposed I could be running both too.

Took her back out for a test drive after replacing the shift lever. Got on it and blew a hot boot almost immediately.....got that fixed up and went back out. She does shift softly.....not saying its bad, but its not the firmness I would expect from a JW.
Ill call GH tomorrow and see if we cant figure that out. It seemed to shift more firmly in the tow tunes than the hotter ones. Never got above 800 EGT even when hot rodding it.
Got some creaking/groaning in the steering...might have to get down there an grease the old girl up. I am just so happy to have a truck again....haha