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G8GT 6L80e Trans Tuning with HPT - The Basics

65K views 28 replies 12 participants last post by  Dousail2 
#1 · (Edited)
This is meant to be a basic guide to get you started with the 6l80e trans, adapted to our G8's, other people with different cars would need to adapt it a little, but it's not complicated once you understand the very basics.

So here we go, please bear with me, as i won't have time everyday to update the guide, this trans is a monster, and as such, there are a bunch of parameters to change, some of them i have no idea what they do, and hence the reason i don't touch them, some others are obvious and easy to interpret. The most important thing to keep in mind, i don't care how many times have you read about disabling the TM to make the car faster, leave that to the trans builders or people who wish to build their trans 4 times a year, i'll show you the basics to have a nice and fast feeling in it, while leaving some TM in, TM is your friend, not your enemy, TM is needed to keep the trans together to a point, she doesn't have to have 100% TM though, but some TM would keep it running for a long time without being too intrusive. most people rebuilding their trans today, are those who thought they were smarter than GM, and that running without trans TM was a smart thing to do because the car is faster without it, there are differences between cars that get trailered in to the track, compared to those of you who DD your vehicle and drive to the track back and forth, being smart is tuning for performance while minimizing the risk of breaking your stuff up, be smart, use common sense, i have 80k miles so far with 10%TM, and i haven't changed one single seal in my trans, other than new trans fluid to accommodate my Yank 3200 stall. I'm expecting to enjoy another 80k miles out of the trans without any drama, that being said, i'm not a trans builder, i don't know how yours would behave, or what's going to happen with it next week :), use common sense, TM can make the car faster to a point, how much faster?, better ask those who keep breaking them, i'm sure they know better...

Anyways, once you get the basics, feel free to do as you wish and go wild or conservative, your choice really. :) Again, i'm not responsible on how you use this info, what changes you do or you don't, use at your own risk.


6L80E Basic Trans tuning Guide

I’m going to divide the parameters we’ll be tuning in 4 different sections or modules as they are defined for us to tune using HPtuners. There are over 450+ parameters we can change in the trans, but that doesn’t mean you have to change them all to have a trans that performs to your likes.
We’ll be concentrating in simple changes that would make your A6 trans more enjoyable.

As an introduction from HPT , Source: http://www.hptuners.com/forum/showthread.php?t=18378&page=2, Post#23 From Chris@HPT

“The trans mostly uses a inertia torque based "profile" to control the shift, ie. it manages the engine torque to try and achieve the desired torque profile during the shift progression (time) and then manages the shift pressure to achieve the desired shift time. You need to remember that the trans has individual pressure solenoids on each clutch *and* a main pressure solenoid (aka force motor on older 4l60e trans).

Starting with the easy one, the main or "Base" pressure is controlled by the main pressure solenoid. This works quite simple compared to the rest of the trans. There are 3 possible pressure patterns X, Y & Z. Each shift mode or type can be set to a particular base pattern defined in the Pressure Pattern Select section. Note that another change we made in this new release was to remove Cruise and Performance tables and replace them with Pattern A Shift and Pattern B shift (note this is a shift pattern *NOT* a pressure pattern and you can see what A & B relate to under the Shift Pattern Type.

So the base pressure X, Y or Z is selected by the current shift mode and then the actual pressure for the shift is controlled by the base tables themselves for each shift. The main solenoid feeds the line pressure to the whole trans, including the clutch pressure solenoids. So you can think of this like your water mains pressure at your house. Raising or lowering your mains pressure does have an effect on how fast the water comes out your kitchen tap but not as big effect as turning the kitchen tap itself (the clutch pressure solenoids).

Sometime GM uses "Discrete Shift Torque" instead of the actual shift torque, to give a less modulated (more constant) base pressure to the main line so that the clutch solenoids and pressure learning is more stable. What this does is define a low, mid and high range for torque and then set the torque number to a fixed value while torque is in the range, so then the pressure lookup in the base table is also constant.

Okay so that's the base pressure... now onto the torque based stuff...

The inertia torque is "factored" into a number between 1 and 9 which is then used later to modify the base shift time and other things. From what i can tell this is the primary thing calibrators use to control the shift "feel" once the main things are calibrated. You'll notice in the Shift Inertia Factor Profile tables, higher numbers are used at higher torque and RPM. Further on in the Shift Time Inertia Adders you'll notice that these higher numbers equate to smaller additions to the shift times (ie. shorter shift times, which equate to higher pressures and firmer shifts). The basic idea here is that the shift is all about managing the rotating inertia change in a certain time between the shafts and clutches as some speed up and slow down during various shifts.

You will also notice that the shift times have two primary type "Normal" and "Special". This is selected by the Pressure Pattern Mode options ie. each of pattern X, Y & Z can be set to shift times Normal or Special.

So you end up with a base shift time + some adders based on inertia torque and other stuff. This shift time is then used to setup the desired torque profile.

The Shift Time Transition Initial controls when during the shift completion (% of shift time) the torque based model starts, then the Shift Time Transition Final controls when it ends - kind of the ramp in time and ramp out time as far as i can tell. Probably used as a way to wait for things to stabilize enough for the torque based model to be accurate, then ramp out once the shift is basically complete. Again, at higher torque and RPM the numbers get smaller.

The desired output torque factors and multipliers control the torque profile itself and experimentation will be required to see exactly what these do, from what i make of it they control the shape of the torque profile as the shift complete's. ie. more torque in the initial shift and less later or the other way around depending on probably a million other things that maybe one person in GM fully understands!

If you have understood anything so far you will realize at this point there are two ways to change the shift feel. Either go in an change the shift times themselves *or* mod the inertia factor profile so that the smaller adders are selected at lower torque/RPM. If you aren't getting good shifts at full throttle then you probably want to change the shift times themselves to be shorter, since you are already at Profile Factor = 9 in most cases. If you just want firmer part throttle shifts and are happy with everything else then maybe just increase the Profile factor from say 3 to 4 or 5 in the mid range torque/RPM areas.

Hopefully by now you've worked out that if shift time controls all this then the pressures must learn to achieve the shift times required, and yes they do. Individual pressure solenoids are controlled by the torque profile and shift time learning, they are adaptive. This trans is *very* good at learning in most cases and this is why you don't hear of many 6L80e trans breaking due to low-mid boost FI applications, unlike back in the 4L60e days which only in some cals had adaptive learning enabled (which was very primitive).

So, you've got the various pattern selects, pressure mode, the base pressure patterns (main solenoid), base desired shift time + modifiers (mostly controlled by calibrated inertia factor 1-9), torque controlled pressure solenoids and adaptive learning to achieve the shift times. Easy huh?!?!?

Please take small steps. You can see now why we were reluctant to add this stuff to the editor as it really does require a detailed knowledge of the theory behind it all and also the operation of the trans itself to fully comprehend what is happening. Even then i doubt there is anyone at GM who knows everything about how this sucker works! (btw, if that person does exist and reads this maybe they can post ”
 
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#2 · (Edited)
I’ll try to make sense of some this concepts and approach the trans tune in a very basic way. First question would be how do we translate this to what I have in my G8GT?, we know our trans have Normal mode, Sport mode and Manual mode, that’s about it.

Like I said before, HPT has divided the trans section in 4 different modules: Auto shift speed, Auto Shift Properties, Auto TCC and Torque Management, fairly simple as we'll see later on.

Auto Shift Speed where we can define part throttle and full throttle shift mph and rpm. This is mainly were you can change your trans shift points depending on Transmission mode (Normal, Sport, Manual), ex: you need to increase your WOT shift point for Sport only, but leave Normal default, , or increase your part throttle shift points for Sport only, or both, or tell the trans when you're getting to a stoplight to make the shift from 2 to 1 in Manual, (in the G8's when in manual, the trans downshift to 2nd gear only, and you have to manually push the lever to M1, you can adjust the shift point so the trans goes from M2 to M1 automatically), in other words, you have a fair amount of control of what you want the trans to do in any mode, at any speed. (obviously common sense apply to what you want the trans to do :) and how do we figure what trans mode correspond to what in HPT for the Shift pattern tables ?

I'll make your life easier so you can memorize it if you have a G8,
We have Patterns for Shift Mode that affect shift speed and Torque inertia profiles, Pattern A, Pattern B, Normal, Special, TUTD, etc, etc, and we have patterns for shift Pressure (X,Y,Z), the TCM can mix everything together to give you the trans feel, trans shift speed, etc. How do we know which one is which ? I'l refer to shift speed patterns here

Normal mode is obvious, Sport mode refers to Pattern A in HPT, Manual is TUTD, Pattern B is not used It's somewhat easy to find out if you have other vehicle different than a G8 looking in the 2nd big section, (Auto Shift Properties /Shift Pressure), Remember the trans has Shift mode Patterns (Normal, Sport, Manual) and Shift Pressure Patterns (X,Y,Z), so if you try to cross match Mode pattern type with pressure pattern, so you should be able to figure this out, sometimes you have adjust one and give it a test, but by know, every tuner by vehicle group know which are the speed/pressure patterns for the their vehicle type.




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Auto Shift Properties, where you are able to see how your shift/pressure patterns are setup, change desired shift times per gear/mode, shift pressures per gear/mode, desired shift time modifiers and torque profile inertia adders., etc, etc. the Auto Shift properties has 3 tabs, General, Shift times, and Shift pressure, it's obvious what some of this tables would do.

Auto Shift Properties/General

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Auto Shift Properties /Shift Times
For Shift speed pattern type, we have a pattern that affects Normal mode, and another that affects Sport mode, you'll find then as Normal for normal, and Special for Sport. when you change an inertia profile in tables that relate to normal, you're adjusting speed for Normal mode, Special affect shift speed for Sport mode, there is no shift type pattern for Manual mode, in other words, you can't make manual faster/slower, modifying shift speed pattern tables, like you do for Normal or Sport, you can increase shift pressures for all 3 modes though.

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Auto Shift Properties /Shift Pressure
Here you can see how Shift pressure patterns relates to shift mode pattern , Shift pressure X related to Normal Pattern, Pressure Y related to Pattern A, which we know is Sport mode, and Pressure Z relates to TUTD Manual, there is also the same Pressure Y that relates to TUTD Auto, easy to figure out right ?, if you change gears in manual, the table pressure that applies is Pressure Z, if you tell TUTD do the shifting (adjusting shift points), then TUTD would use Pressure Y

So Normal mode uses X pressure
Sport mode uses Y pressure
and TUTD uses Z pressure.

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Auto TCC Where you can change Torque converter apply/release mph/rpm, enable/disable lookup, etc.
If you have an aftermakert verter, or want to get rid of the G8GT 50mph bouncing rpm while on decel, here is where you change stuff up to fix it.


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Torque Management where you enable/disable TM, change TM various settings like TM adders/multipliers per gear, etc.


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To be continued...
 
#3 · (Edited)
Following the 4 HPT trans modules we've already explored, we'll proceed to tune the trans, using the Auto Shift Speed to affect the WOT shift points, The Auto Shift Properties to make the trans a tad faster and firm, the Auto tcc to make some adjustments to the stock verter/aftermarket verters, and the Torque Management module to remove some TM.

Making the trans shift faster
Please use common sense here, the 6L80e trans can be set to shift faster, we can decrease the times it takes for the trans to perform the shift. With a decrease in time, an increase in shift pressure is also desirable so the clutches have what they need to get applied. how much can you decrease time from the shift and increase pressure to the shift is the million dollar question, i wish we had some sort of formula we could use to say, decrease xx ms from the shifts and increase xx psi so the clutches get what they need, and the trans react this way or that way. Unfortunately this is not the case, i'm sure somebody at GM must know, but this information has yet to be made public :), so we have to resort to trial an error.
Per Chris notes :

from Post#1:

"The inertia torque is "factored" into a number between 1 and 9 which is then used later to modify the base shift time and other things. From what i can tell this is the primary thing calibrators use to control the shift "feel" once the main things are calibrated. You'll notice in the Shift Inertia Factor Profile tables, higher numbers are used at higher torque and RPM. Further on in the Shift Time Inertia Adders you'll notice that these higher numbers equate to smaller additions to the shift times (ie. shorter shift times, which equate to higher pressures and firmer shifts). The basic idea here is that the shift is all about managing the rotating inertia change in a certain time between the shafts and clutches as some speed up and slow down during various shifts.

You will also notice that the shift times have two primary type "Normal" and "Special". This is selected by the Pressure Pattern Mode options ie. each of pattern X, Y & Z can be set to shift times Normal or Special.

So you end up with a base shift time + some adders based on inertia torque and other stuff. This shift time is then used to setup the desired torque profile.

The Shift Time Transition Initial controls when during the shift completion (% of shift time) the torque based model starts, then the Shift Time Transition Final controls when it ends - kind of the ramp in time and ramp out time as far as i can tell. Probably used as a way to wait for things to stabilize enough for the torque based model to be accurate, then ramp out once the shift is basically complete. Again, at higher torque and RPM the numbers get smaller.

The desired output torque factors and multipliers control the torque profile itself and experimentation will be required to see exactly what these do, from what i make of it they control the shape of the torque profile as the shift complete's. ie. more torque in the initial shift and less later or the other way around depending on probably a million other things that maybe one person in GM fully understands!

If you have understood anything so far you will realize at this point there are two ways to change the shift feel. Either go in an change the shift times themselves *or* mod the inertia factor profile so that the smaller adders are selected at lower torque/RPM. If you aren't getting good shifts at full throttle then you probably want to change the shift times themselves to be shorter, since you are already at Profile Factor = 9 in most cases. If you just want firmer part throttle shifts and are happy with everything else then maybe just increase the Profile factor from say 3 to 4 or 5 in the mid range torque/RPM areas"

Here are the base shift times, you have tables for normal and special, as i said in post#2, normal in the tables apply to normal mode in the trans, and special apply to your Sport mode. you can increase or decrease shift time and pressure to Normal and Sport mode, and increase/decrease pressure from manual mode only.

Normal and Especial refer to shift times, inertia profiles intertia adders, etc, etc, are all time referenced in ms (miliseconds), you have tables that affect upshift and downshift, and this can also be setup per gear, 1-2,2-3, 3-4 4-5,5-6, then 2-1, 3-2,4-3 etc, etc.

Then you have tables that control shift pressure (pressure pattern) defined as X Y and Z

As i said in post#2
Pattern X control pressure for Normal mode
Pattern Y control pressures for Sport mode
Pattern Z control pressures for Manual mode or TUTD

Pattern Y and Z share the same pressure pattern mode, this means pressure patterns Y and Z applied to shift pattern Especial. Pattern X applies to shift pattern Normal.

So how can we mix all this info together ?

Note, i don't change anything here, but for the purposes of general knowledge, in case you decided to change things in this table, here is the table that Chris is referring to in his Quote, Inertia Factor profile, if you look at this table, it has those values from 1thorugh 9, from 0 to 6400 rpm, and -30 through 413 ft.lb, (engine requested torque), so the higher the rpm and requested tq, the numbers move from 1 to 9, once you look at the next print screen, you'll understand why.



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How can i translate all those numbers from 1 through 9, if you look on the shift time tab, you'll find your answer, applying to Normal or Especial shift pattern, per gear, upshift or downshift. this are the tables i modify, i leave the ^ stock, but i modify the base shift time, and the inertia adders to effectively remove shift time and affect trans feeling.

The lower the numbers, the fastest she'll shift, and also the firmer the shift would get, the trans can be too jerky if it made to shift to quick, so jerky that some people like me would hate the feeling, some others would love it, up to the tuner really and what you want out of the car, the feel can be adjusted to suite your needs. as a rule of thumb, lower the numbers from the profile 7,8 and 9 (this is WOT if you look at the inertia profile tables, at high-max engine requested torque)

Keep in mind i don't touch the inertia adders for downshift tables, nor i modify the inertia factor profile for downshift, if you do so, please be aware than making this tables faster can actually cause a big delay from your downshift, or make it stupid bad jerky, cluncky or worst, i simple lower the base power downshift values a little, splashing your fingers all over the place around here is what confuses the shiat out of your trans, be gentle to her, start small, test and observe, you don't have to change everything here to zero because the new Camaros or vettes have all zeros, or change every little table for upshift or downshift, Look at the tables to the right of the base shift tables, i've enclosed them in blue or green as an example to make the whole thing make more sense, that's how they add/remove time from the base shift tables, per gear, upshift or downshift.

Below you'll find an example, base shift time for Normal mode 1-2, inertia adder normal 1-2, and Output torque normal 1-2, there are other things like the shift time transition intial and final for normal and sport that also add/remove time from the shift. I've modified those in mine, but you'll have to experiment, only after you've set your base and inertia adders. they modify shift feel, so change them at the end so you'll realize what they'll do do the shift feeling, it's hard d to tell, but changing this values would change the moment the clutches are about to get applied/release.

In the G8's, GM used the base tables, plus the inertia adders, and output torque factor tables, to have the shift/feel coordinated. splashing your fingers in this tables would upset the timing balance :), or zeroing the base when the others tables are adding/removing time from the base, would make for a very discoordinated trans, you might now about it because she WILL shift like complete shiat. A good tuner is not the one that can make her shift fast, but one that can accomplish that and make the trans last.




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In a general way, this is what i did in my application
Removed more or less 5 ms from the base shift time table for normal and a couple from the inertia adders in normal, and some more for Especial, (normal is almost Normal, special is way faster), and made them more or less all the same values, (from input from a guy in HPT who rebuild trans for a living and gave us that advise :)) only for the single upshift gears (1-2,2,3,3-4 etc, leave the 1-3, 1-4, 2-6 etc alone, she would shift crappy if you touch those, ask me how i know), this reflects some of the changes i did for the upshift normal and especial, you do as you want since you're learning how easy this is.



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More to come...
 
#4 · (Edited)
Now we're going to take a look at trans pressure.
Refreshing some of the concepts as explained by Chris@HPT

"The base pressure X, Y or Z is selected by the current shift mode, and then the actual pressure for the shift is controlled by the base tables themselves for each shift. The main solenoid feeds the line pressure to the whole trans, including the clutch pressure solenoids. So you can think of this like your water mains pressure at your house. Raising or lowering your mains pressure does have an effect on how fast the water comes out your kitchen tap but not as big effect as turning the kitchen tap itself (the clutch pressure solenoids)."

Trans -> Shift Properties, Pressure Pattern Select
This chooses the Pressure Pattern (X/Y/Z) based on the current Shift Mode. This mostly controls just the base pressure.

Trans -> Shift Properties, Pressure Pattern Mode
This one selects either Normal or Special mode for the clutch control shift parameters. This is where the main shift quality differences are programmed. eg. Usually Normal will have longer shift times, lower pressures and Special will be shorter/firmer shifts.

Note: Don't change anything in this tables, this is how GM wired the controls for pattern pressures for your car, this would be different among other cars like the Camaros, vettes, trucks, G8's etc. this is how you can realize what Pattern pressure X, Y or Z means in your calibration.

********* So for shift pressures, we know X affects Normal mode, Y is for Special, and Z is for TUTD mode *****************

In green are the things i've changed in shift pressure with respect of the stock calibration.



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Some definitions i've found in HPT

1.Max Pressure - Limit/Clamp on the values in the Max Line Pressure Table
2.Max Pressure B - Limit/Clamp on the values in the Base Shift Pressure Tables
3.Max Clutch - Limit/Clamp on the TCC Pressure Table
4.Max Line Pressure - It appears as though Max Line Pressure is controlling the feed pressure to the Force Motor Valves (62,64) which generate the Pressures commanded by the Base Shift Pressure tables.
5.Base shift pressure - Base line pressure per gear and pattern select (Normal,Sport,TUTD)
 
#5 · (Edited)
Trans TM, Explained from Chris@HPT
a good place to start would be with the Cold Shift Factor tables. Usually they are 1.0 at the highest temp. This factor is the last multiplier and should see an differnce for all upshifts). Use this just to test things out, once you are happy with what to change and how much to change it, probably best to set the Cold factor back to stock.

Making the numbers closer to 0 should result in less torque reduction.

Some more detail:

The Final Torque Factor is calculated like this:

FTF = {Shift Torque Factor + (Shift Torque Factor Adder * Shift Torque Factor Adder Mod)} * Torque Factor Cold

Shift Torque Factor is per shift & usually in most cals set to 1.0

Shift Torque Factor Adder is per shift, it is multiplied by the Shift Torque Adder Mod before being added to the Shift Torque Factor.

Shift Torque Adder Mod is a table with RPM & Driver Demand Torque. It is used to scale the Shift Torque Adder depending on RPM/Demand Torque To give the different shift feel. In some cases this table is 0's in others it changes the shift at lower RPM/Torque. Remember it is the combination of all these factors that ends with the Final Torque Factor.


Torque Factor Cold is used to account for cold trans temp. You can see in the forumla above it is the final multiplier of everything. So it will be a good place to start. ie. leve everything stock and set the cold factor to say 0.75 and then 0.5, 0.25 or 0.0 or something and see what happens. Then set it back to 1.0 and try to refine it further using the individual factor, adder and adder mod.

Also, the desired output torque tables control the profile of the torque during the shift and you'll need to experiment with those as well as these new params to get what you want.

Hope that helps,

Chris...
 
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+8 Reserved
 
#13 ·
This is gonna be an amazing sticky!! Thank you for putting this together!
 
#15 ·
Subscribed!
 
#16 ·
Sorry i haven't updated guys, i've been super busy at work, i'll try my best to keep adding things this week. I've had some changes in the family in the past week as well, lol, everything is cool though, and everybody is healthy, but i had to cancel the cam order i had :(
It's a shame, but it was for the best, My next try to do the cam and pay for the install would be Jun 2013, damn it, but oh well, i'll have my hands busy with the new family addition.
 
#18 ·
Congrats on the addition!! I know how that goes. Have you considered doing the install yourself? That would save you a ton of coin!

Thanks again for this write up. Its a great confidence builder. Ive also been reading your other one on engine tuning as well it is great!!
 
#20 ·
Tjay i saw your PM, i just haven't have a lot of time to catch up with everything i'm doing,
Have you look at the tcc desired slip tables ? if not start there, and zero them out for every gear.
 
#21 ·
Will do, I found one of your posts on the HPT forum and followed one of the replies you made where you zero'd the 4, 5, 6 gears out. I am trying that for now. I put the shift times at .200 in the upshift and downshift tables and put the codl modifier table at .750.

So far so good, I tried .500 in the codl modifier table and while the truck had more power during the shift it was brutal and I really dont want to try and break anything due to a shift.
 
#22 ·
If it is ok with bluegoat can you link his thread on hpt here? Or pm it to me? I will be taking the plunge soon and I want as much reading material as I can get!!
 
#24 ·
6L80E Tuning Observations/Questions

I know one of our resident tuning gurus (Bluegoat) has been busy, as well as distracted by a new car, but I hope we can keep this thread going, as it is a good resource for tuning the 6L80E transmission via HP Tuners. Before starting a new thread, I figured I would take a gamble on how much traffic this thread still sees. I know many of you have more experience than I, and hope to gather your advice. I wanted to post a few of my own trans tuning observations as well as ask a few questions.

First off, my tuning goal is more focused towards dialing in shift feel to my liking than lowering shift times by a maximum amount. My goal is to have a car that shifts quickly, firmly, but in a controlled, never jerky manner.

My first goal was to quicken the shifts and add firmness. As a starting point I lowered shift times in sport mode. This resulted in a very noticeable difference in trans feel. Shifts were faster, slightly firmer, but not harsh. Common sense leads me to believe that for the transmission to complete a faster shift, base shift pressures most likely need to be raised as well. Thus, I raised base shift pressures by 30 or so psi at high RPM& torque conditions, but couldn’t detect an obvious increase in shift pressure while driving. I know the base shift pressure tables are below the Max Pressure B limit, so the problem isn’t there. I have heard to not mess with the max line pressure table, but instead raise the Max Pressure B limit and use the base shift pressure tables to alter shift pressure. This leads me to my first set of questions. Are the base shift pressures a maximum value the trans will use if needed to make a shift? Or are they where the trans starts, and then adjusts to a more correct value using volume adapt parameters?

Next, I looked into using the shift time inertia factor, shift time inertia adder, and shift torque time adder tables to tailor shift times across the RPM range. Shift time appears to be equated by a formula that takes base shift time plus a few adders. From digging around in HP Tuners these adders seem to be limited to shift time inertia adder, which adds time based on the inertia factor profile; and shift time torque adder, which adds time based on a table of RPM versus torque. Driving the car showed that adjusting the time values in this table allowed low RPM upshifts and downshifts to remain slower and smoother, while high RPM shifts are still quick. My question on this topic is the difference in torque profiles these two adders use. The shift time torque adder is based on “input torque”, and shift time inertia adder is based on “driver demand torque”. Both use different values in the vertical torque axis of the tables. How do input torque and driver demand torque differ? Can the values in the axis of these two tables be adjusted to be identical without adverse consequence? IS one used instead of the other during specific driving conditions?

Lastly, I used the equation Bluegoat posted to adjust the level of torque management. This made a monumental difference in the feel of the shifts across the board. None of the previous changes broke the tires loose on the 1-->2 WOT shift. After altering TM, the tires now bark on this shift (a little too much for my liking). The trans now shifts in a very spirited manner under heavy throttle, but not too harsh. Part throttle shifts are now firm but not jerky, and low throttle/RPM shifts are smooth. My question on this topic is if quicker, better feeling shifts should be achieved by setting and leaving TM settings low to reduce the timing pulled and further adjust shift feel via time and pressure settings, or if TM should remain a forefront parameter to adjust shift feel?
 
#26 ·
can any changes be made to just affect the tutd manual mode to shift firm and faster and not change the normal shifting ? also where do I find the rpm match for down shifting in tutd mode (z) lastly any way to get the images in the post ? thanks gmonde
 
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