
Originally Posted by
farmtruc
I'm not trying to change what you think and feel about the trans or questioning your ability to build them, I'm responding to the fact that you said the tune was off, without looking at it.
I know of master trans mechanics and guys who claim to have built expensive transmissions as well, but that doesn't mean they know how to tune them. They know how to build them! I'm not saying you don't know how to build or tune them either, but that's what you're saying to me.
As far as certs, well I just looked at my tuning database and I guess the 170+ A6 transmissions I tuned in '07 that haven't burned up and the 68 A6 trucks for '09 don't count, oh well.
Acceleration limit and Commanded tq tables limit the trucks ability to produce power and accel. Most ppl just call them TM tables. Weird results happen when TM shows it's ugly head. It's up to the ecm hackers to find those tables, not us.
What I was referring to resides in the ECM.
Let's break down the tables that hptuners and efilive have given us to tune.
That's what I'm assuming you're using, right? These tables are available for editing, but that doesn't mean the hackers have it right, they don't define how GM's OS logic works, they just give us the ability to change some tables.
On the first tab I see Shift Speed. Wow, just a bunch of shift patterns that allows us to change when the transmission shifts based on MPH and Throttle position and what position the selector is in. There is also tap up and down control with rpm based shifting at wot. Not any real magic here, just looks like more shift tables to me. BUT, working these tables will surely make a truck feel much better.
Second Tab first column has to do with shift speed or time.
Knowing these tables will allow for quicker shifts.
Each table and tab is labeled, so just read and alter the shift speed, however, know what you're changing and keep in mind, changing tables according to what the definitions says, doesn't mean that's what will happen.
Third row, shift pressure. Has all the wonderful shift patterns for each axis and gear based on temp and torque. Again, more complex, but it comes down to, the more pressure at the right time, the better/firmer the shift. Again, know what you're changing before you alter the tables. I see Adaptive learning, either way is fine, turning it off just allows more predictable control, but I leave it on.
General Pressure tab, empty.
TCC settings, same crap as always, just two more gears and more tables to tune.
TM tab, well, it's TM, increase the tables and disable the drop downs. I change most of these tables, but leave three alone.
I know this was long and drawn out, but show me where all the magic and crazy stuff is in the calibration that we have access to. Granted, there may be more hidden tables, but what is there is straight forward, just like all the other transmissions in the past.
I'm not saying the A6 is less complex, but you or I do NOT change the code and logic GM has set. We simply change what is given to us. We're not here to rewrite the OS.
That is where the transmission class comes into play. You probably understand every electrical pulse and function of the trans, but you don't get to tune that, do you? You probably understand all the logic and all the mechanicals, that's awesome! BUT, you're still left with using a program that anyone can buy and learn.
Unless you have some crazy ass application from GM that alters every aspect of the GM OS.
I'm sure a class for the new transmission would be nice, but I don't care to build transmissions, you do.
What you/me need is a transmission tuning class, that links building a trans to tuning a trans.
btw, check the hptuners.com website, a lot of ppl are having the same issue.
Does that mean every shop out there doesn't know how to tune the new A6 trans?
What we're facing is something like COT, way back in the day. Tuners wanted to know why a/f ratio was going rich during a hard wot run, well, after the hackers found the table that disabled COT, it was easy.
Same thing here, there is a table that is interfering with acceleration or torque output and doesn't take a master builder or tuner to fix it.
We'll have to wait for hptuners, in my case, to figure it out based on feedback from tuners like me and you.
and omg, you just made me type more words in a post than I ever have, thanks! lol.
later,
allen