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Hey guys,

I am going to be heading to the dyno this week for some tuning time. I am still pretty new to the whole tuning aspect of the car.

Chris Y and John T have been helping out with the AFC 2.0 and it is much appreciated. I feel comfortable in what I have currently on the AFC, now it is time to go to the dyno and get it finer tuned.

Here's my question(s).

What # should be the target on the wideband? I am hearing everything from 11.5-12.4 Someone was saying the "Prime" is 12.1

When making the first pull, it will come up with #X...and then an adjustment will be made on the AFC. In the past, i have been taught that an adjustment on the AFC takes approximately 20-30 miles to be "learned" by the PCM. If an adjustment is made between pulls, will the PCM "unlearn" the adjustment just made? Or will it stick??


I do plan on having HP Tuner Suite in the very near future, but for now, I wanted to get a # on the dyno as a base.

I plan on running the dyno on 93octane with a 3.1 pulley. The car seems to be really happy with that on right now. Over the weekend I was fine tuning the AFC (or as fine as I can get) and was seeing 0KR with LTFT at 0.8 and B1S1 @ 915-920.

From there, I would like to tune down another pulley size in a couple of weeks. That way I know what #'s to go back to in the future.
 

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Well, I don't have a lot of insight here, but I do have a little.

You basically want to get about as lean as you can without knock. This will obviously depend on your mods, and your engine. There is a wide A/F range that will only gain you a small amount of power, so I would shoot for the safe end of it. 12.1 sounds like a good starting point. Start there, and adjust leaner/richer depending on how it reacts.

As far as the PCM reaction time to the AFC, I thought that as soon as you make the change, and cycle the ignition, the PCM will start adjusting... I could be wrong on that, though.
 

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The pcm doesnt 'learn' the afc adjustments. Basically all it does is skew the table thats in the maf.

Laymans terms.


Maf freq = a
AFC adjustment = b
PCM sees = a+b
 

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Steve, I would aim a little lower like 11.8.

Any change to the AFC will show up on the next pull. As long as you only make changes to the WOT settings (high MAFs) you shouldn't have to worry about changes getting "learned out" later since the LTFT's immediately before going into the WOT trim cell should remain unchanged.
 
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