Typically this is set to 1.0000 in all cells, but a local tuner keeps setting mine to .2998 or .02xx. Why?
The formula for tqmgt is: FTF = {Shift Torque Factor + (Shift Torque Factor Adder * Shift Torque Factor Adder Mod)} * Torque Factor Cold
My guess is he doesn't notice that I have a custom "Shift Torque Factor Adder Modifier" table.
Thoughts?
My guess is because a stock G8 has the Adder Modifier table zero'ed out that he thinks hes pulling tqmgmt?
2009 G8 GT - White Hot
226/234 601/601 112+4, Yank SS 3600, SLP Longtubes, Magnaflow exhaust, Rotofab, 3.91 Rear
I've never really understood exactly what the "Shift Torque Factor" signifies... Does reducing it reduce or increase the amount of torque allowed to "pass through" during the shfit? I understand how most of the adders and modifiers work, but not the "Shift Torque Factor" itself...
Anyone care to help explain it?
There are 100 threads on trans torque management. Here's a hint: Look in the engine section.
One thing that I don't quite understand with my stock tune is that the "Shift Torque Factor Cold" is lower the colder it gets. It's not until the trans temp hits 86F that it is set to 1.0000. Why in the world would they want to reudce the amount of torque management when the trans fluid is cold?
For example, at 14F, they Shift Torque Factor Cold is ".6504", at 32F it's ".7002", at 50F it's ".7002", at 68F it's ".8750" and finally starting at 86F it's set to "1.0000".
I would have thought that it would be the opposite and you'd want more torque management the colder the trans is??
Anyone hae any insight into that?
Thanks for that link - lots of great info in there.
It looks like there is conflicting info about the "Shift Torque Factor Cold" - one person said to halve the values and another person said to leave them set to stock values. Does it make sense that there should be less torque management when the trans flud is cold?
Also, I'd assume that one you get past the highest temperature in this table, then it would no longer be used, so I'd think that this table is meaningless over 104F in my case (last value in my Shift Torque Factor Cold table). Agreed?
Regardless, like I said, thanks for sharing that link - LOTS of useful info all in one post. Good stuff.
It's a case of there being more than one way to skin a cat. It's not nearly as cut and dry or linear as tuning spark and fuel.... tuning the engine is very quantitative. Tuning an auto trans for driveability is very qualitative.
You have to look at other factors in cold shifts rather than one thing at a time. Remember, everything works together. Spark adders, shift pressures, torque management, shift speeds, closed loop switching modifiers, and so on.
You can't edit a table in a vacuum, so to speak.
Yeah, I get that there are multiple ways to do the same thing. But, surely there is a "definitive" answer as to how the cold multipler table works - meaning is the table ignored once you get past the highest temp in the table? Does the table become meanlingless after that temp (104F in my case)? Being that it has the word "cold" in the title, I'm assuming it only comes into play below the highest temp (aka when the trans fluid is "cold"). So tuning that table is somewhat limited in function, I would think (only important for the first few minutes of driving - depending on the outside air temp, of course).
all tables in hptuners work the same way. the last cell applies to all values greater than that cell.
read up more, use search, there is more than enough information on this forum just like the link i posted which was supposed to get you started. we have all had to do the same thing, otherwise, we are all writing the same book over and over again.
Oh, believe me, I've done TONS of research and reading (for months now), but sometimes I just can't find answers to some of the more specific questions I have. For example, I've never seen anywhere that says that the last cell in a table applies to all values greater than that cell. And in this case, that doesn't even make sense to me. Why would a "cold multipler" table affect the trans for all temperatures. If that is the case, then it's really not a cold multiplier table - it's just a "temperature multipler table". :-) It also doesn't make sense to me that after 104F you can't control that value - unless it really onyl applies to temps below 104F (which does make sense). I would have never guessed that (and have never found anywhere that says so) - that's why I ask these questions - believe me, it's not for lack of trying to find the answers! :-)
I appreciate the assistance. While all of the answeres may be out there somewhere, theres not always a practical way to find them - which is why someone liek you can be very helpful.
Now - at the same time, I do ask a stupid question at times (like the question about the 'shift torque factor" - I should have known that one as I've read abotu it multiple times in the past - just a lot to learn though, so sometimes a simple yes or no answer is so beneficial.
Again, thanks fo the help.
No worries.
It doesn't control it for all temperatures. The last cell value is what controls higher temps, which is, it doesn't affect them at all because the value is 1.0 and we all know multiplying something by 1.0 doesn't change that something. It's just a multiplier table, not a base table. Don't hold it in such high regard, lol. You should be using base tables to control whatever you are tuning at normal operating temperature. Modifier tables are just used to modify the base tables for special circumstances outside of whatever is normal.
Understood that it doesn't affect them at their stock values - but if I cut all of the "shift modifier cold" values in half (like was mentioned in the link you provided), then it would affect all temperatures since the highest value would be .500. Which, if it then affects 104F and higer, it would end up reducing the torque management by 50$% at all temperatures higher than 104F.
That's what I'm trying to understand and what I assumed that above 104F, it wouldn't affect the final torque factor - becuase if set to anything other than 1.0, then it would affect all temperatures and not just "cold" temperatures (if the last setting is used for all higher temperatures).
I tried reducing it (cold multipler table) by 25% today and didn't really notice a difference in the shfiting. Will have to review the logs to see what effect it had.
It's the little details that are so hard to get answers to sometimes. And I'm a complete noob, which I'm sure doesn't help! :-)
make sure you also know what your transmission temps are. log that too.... you'd be surprised how long it takes to get over 100 in daily driving/cruising.
I do monitor transmission fluid temp and with this vehicle (FWD), from a "cold start" this morning (for example), it takes only 7.5 minutes to get over 100F... Since I prefer "soft" shifts (unlike most on the forum), I actually tried setting the cold multiplier table back to stock and *increasing* the STF values for 1-2, 2-3 and 3-4 shifts from 1.00 to 1.10 today and I really liked the results. Was a very short trip though (12.5 minutes, including a stop at a gas station!), so will keep monitoring... But I think increasing the amount of torque management instead of decreasing it is going to give me the results I'm looking for (I'm looking for "comfort" over "performance").
My VCM scanner config and log file attached from this mornings trip, if interested in viewing it. Was a very "easy" drive - no WOTs or anything like that - just driving normally.
2012Impala-TransmissionScan.cfg
051115-v1.27-ToAndFromGasStation.hpl
i didn't realize the car you had. i haven't tuned any fwd's except a few cobalts.
Yeah, I haven't tuned any other FWD's either (or ANY other car for that matter!). ;-) I should have mentioned that I'm working with a 2012 Impala (3.6L V6, 6-speed FWD) - especially since I'm in the V8 section of the forum right now! Just not much going on in the V6 sections, so been reading a lot about the 6L80 trans and trying to apply it to my 6T70.
I must say though, I've learned SO MUCH about the way things work by researching and messing with the HPTuner VCM Suite. I absoutley love being able to tweak just about anything in terms of engine/transmission! I've learned more in the few months I've had HPTuners that I've learned in the previous 41 years of my life! :-)
Just takes TONS of research, TONS of time "experimenting" and TONS of time reviewing logs. I've VERY careful about what I change, change things in small amounts and like I said, review LOTS of logs - but I'm definitely learning - with the help of you experts on the forum!
Last edited by jtrosky; 05-11-2015 at 01:03 PM.
Sorry to completely hijack your thread here... But I would have to agree with you that he's probably trying to reduce torque management "globally" per shift - like you said, he probably just didn't realize that you had "fine tuned" the torque management with the sift torque factore modifier/adder tables.
That being said .02 values in the STF fields is awfully low (2% toruqe management!). I'd be very weary of using that low of a TM value for any shift!
Originally Posted by Allmachtige
I agree, "shift modifier cold" completely eluded me until someone explained it. I wouldn't have even known it was there until Russ suggested changing it. It's a deceptive name, because it's really controlling all temps, but specifically references the cold temp ramp up.
@ Higgs Boson - I've had a burning question I can't find a solid answer to: In automatic transmissions, is the shift torque management actually protecting anything or just there for feel?
I keep going back and forth between turning off TM completely (it's not harsh, but it's much quicker in acceleration) or keeping it turned on (in a reduced state) to protect the transmission longevity.
2017 Chevy SS 6.2L/6M
I know that you are looking for an answer from someone that has more experience than me (don't blame you for that!), but I have read multiple times (from the experts on this forum and others) that you should NOT completely disable TM on the A6 trans. The experts all seem to agree that some TM is required to protect your transmission over the long haul.
Again - that is what I've read - obviously, I don't have the experience to know for sure though.
I absolutely appreciate that, I'm just looking for "why" one way or the other. A number of tuners here recommend turning off all TM on the RWD 6L80, which is loosely (emphasis on loosely) related to the 6T70.
I really like the shifts without it, from a performance and feel standpoint, but I need to know what I'm doing to the transmission for both my own sake and especially before I share this tune with anyone.
2017 Chevy SS 6.2L/6M
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