I've ordered an Xcal 2 from TP, hopefully to arrive soon, and was just wondering about something..

I understand the need for the pcm to adapt to the new tunes over time, but my question is this:

Once I've loaded a particular tune, and the pcm has "learned" the new parameters, will this adaptive period occur again every time I change the tune? i.e., if I return to stock tune from 87 perf. and then back to the custom tune will it still require the learning curve as when it was originally loaded? Or even when switching from perf. to tow and then back?

Thanks for any input!!

 

The short term and long term tables should not be lossed but begin to adapt/shift in response to the the program changes and your driving habits.
These tables 'are' reset to their base programmed values if you power down the PCM.
Then they have to rebuild again.

 

All KAM is cleared on a re-flash. That includes fuel trims.


I have to ask, where did you get your information Bluegrass???

 

Tex, Good question, I was wondering the same and noticed my tunes improve a lot with regard to smoothness/driveability after leaving them alone for a while.

i.ride, what is KAM? Are you saying every time you re-flash the process starts all over? I'm pretty new at the tunes and don't know all the lingo.

I had a horrible 3-4 shift which faded after a while of running the tunes. This is gone now with both tunes I run but it took a while to get rid of it, however re-flashing between 87 and 93 or even stock and back does not bring it back. That would lead me to believe at least some memory stays in the tune between flashes.

 

If that is the case i wouldn't say your tunes are 'good', but they work. If your tunes were 'better' the less the PCM would have to learn and correct.

KAM = Keep Alive Memory, Yes.

 

Bluegraas is correct, This is a true statement for 98 through 2003 trucks. I am not sure what the o4 and newer
computer system remembers and what it forgets. I have had quite a few tune upgrades through the years, and one thing I have found if the tune has a lot to learn it isn't right, and no matter what it learns it won't be right. When it is really off after getting better it will start do get worse.

 

Interesting..

Have you any experience with Troyers tunes in this regard? It's not anything that would scare me off, just something that I would probably feel aggravating..

On the other hand, I'll probably install the 93 perf tune and just leave it there unless I need to take it in to the dealership..

 

Tex,

I should note that I don't have my TP tunes yet but have wondered the same thing you asked.

 

I first loaded the 87 performance before changing to the 91 performance...it seemed to adapt to the 91 performance much quicker than the 87 performance

might be because some of the changes had already been learned but do not have enough knowledge to just say that

 

I have a highly modified truck and MUST run with a custom tune, I cannot run the truck with the stock tune. Yes all my tunes have been Troyer tunes, I have always had 3 tunes but the only one that I ever use or have used has been the 94 octane Max performance tune, and have never even as much as tried the other two tunes. Once the tune has a few hundred miles on it I hate to do anything to change it. Mike had massaged the first set of tunes for me a few times with a lot of data logging on my part, we both spent a lot of time and effort to get things close, and keep things safe. About a year ago, after changing boost levels and a few other things I decided it was time for a new tune. I contacted Mike and he agreed that we needed to address a few issues. Mike hit the tune quite well and other than a slight cold weather drive-ability problem, I believe the tune is as close to perfect without being on a Dino. If he ever finds time to take care of the cold weather hesitation issue it will be excellent. Mike is a little too busy now to do this type of tune without being on his Dino. If I had the time I would take it to him, but that is out of the question with my schedule. I would doubt that many tuners would even do a mail order tune of this complexity without having it on their Dino. Again I must add that I can only speak for the pre04 trucks the new system is quite different.

 

Damn Chuck, what sorta rwhp are ya layin' with all that?

As I'm sure you can tell this is my first venture into custom tunes, I'm fixin to start jonesin' over gettin' the things installed.. lol

Christmas in October and all that!!

 

Be careful, the modification disease is incurable, the only way to slow the spread of the disease is to amputate you're wallet!!!