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Auto Tune

DEP47

Member
I would like to know more about how the Auto Tune tuners work. I know they read the sensors, and make adjustments, but what are they adjusting to? Do they make adjustments to the base map installed, or to some AFR? Do these tuners ever go into a closed loop mode? I am sure the different manufactures may do things differently , but I would assume they are all trying to achieve the same goal, but I can't find anything in writing as to what the auto tune systems are actually trying to achieve. Thanks.
 
I know they read the sensors, and make adjustments, but what are they adjusting to?

Your question is multi-part but the bottom line is this.
It is very similar to a person playing against a computer in a game of chess. The computer can not make logical decisions based on emotion and so the computer can only be as good as the "set of program steps" that were entered into it.

Auto tune is exactly the same thing. Auto tune systems will hunt and adjust for "target" or ideal values BASED ON THE TARGET VALUES WHICH WERE SET BY THE PROGRAMMER.
Therefor unless one programmer is looking over the shoulder of another, no two auto tuners will be exactly the same.

Resolution of target values is another very important decision the programmer must make. Some systems require large jumps in sensor values before a new entry is made into the table. Some systems (such as the SEST) do not. The smaller the value, the better. But higher resolution systems cost so much more in time to develope.
 
Thanks, that is what I assumed, but how do we know what parameters the programmer has selected. Seems like it would be good to know targets for timing and AFR should be known?
 
but how do we know what parameters the programmer has selected.

One way is to ask the company who developed the unit but more than likely you will only get a very broad and general answer. There is no good reason why the programmer will give you the detailed answer your looking for because it does him no benefit and only raises more questions he will have to answer. Plus it boxes him into a corner if the system does not perform well for you. Remember that the object of the game is to give you enough information to entice you to BUY it.,,,Not to give you enough information to allow you to do it yourself without their help.

Also remember that each different engine configuration requires a complete different set of X-Y coordinate values or target points. He may have the 96" with VH exhaust and 255 cams nailed down to perfection,, but his 103 with 203's w/ true duals file may be garbage.

There are lots of branches to your question and the answer is not simple.
 
That is about what I thought, without this information, seems like the auto tune could be a great option, or a problem. Guess I will stick with my Dyno tune until I can get more information. Thanks
 
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