General questions about fuel map / tuning

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Sofa King
 

Posts: 6
Joined: Thu Aug 08, 2013 5:58 am

General questions about fuel map / tuning

Post by Sofa King »

So, i'm in the process of tuning my KA-T.

I have it running fairly smoothly, to be honest, but I feel like I am still not quite grasping a lot of things, and feel like it could be running a lot MORE smoothly, despite my already somewhat successful basic tune.

For instance, on the fuel map, there's the dropdown box where you can select "RAW VALUES" or "ESTIMATED A/F RATIO" or "DUTY CYCLE" and whatnot. I've gathered that the ECU reads the "raw values".

I idle at roughly 14.7. When I hit boost (As little boost as possible. Lowest I can set it at is 7 psi. Afraid to go higher currently), I start running richer, all the way down to 11. (These AFR's are according to my wideband, not nistune)

The thing I don't understand is that if I look at my fuel map in "ESTIMATED A/F RATIO", my idle cell is at like... 9.80, even though my wideband is registering ~14.7
Do I need to be concerned that the "ESTIMATED A/F RATIO" is nowhere close to what my -ACTUAL- AFR is? I've just been adjusting the raw values until things run how I want. I should add that I do -NOT- use an o2 sensor. I -only- use a wideband and set everything how I want in nistune. There's nothing stopping me from putting in an o2 sensor, I've just had a few people say that with software like Nistune or AEM or Hondata, you want the system to do what -YOU- tell it to do, instead of what an o2 sensor might be trying to tell it.

Also, I haven't messed with input tracer yet. Is that just a sort of "temporary" tuning tool for when you're on the fly? Like... does it just show you what cells were utilized during a pull, and you change things in those cells if they aren't where you want them?

Also, how is the knock monitor used? Can it even be used, or do I pretty much need a knock light? My buddy is trying to talk me into buying AEM EMS2 because you can monitor and log knock easily.....I think AEM is a bit too much for my needs.

I'm open to any and all tuning advice, and would prefer it. Processes, steps to take, etc.. I've searched around but wasn't able to really find satisfactory answers. :/

Any advice is appreciated.
Matt
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Re: General questions about fuel map / tuning

Post by Matt »

This is why I remove the 'estimated AFR' display from the Basic User mode. As to avoid confusion

Focus on the actual AFRs from the wideband. Usually we notice that if the fuel trims (when O2 sensor enabled) are close to 0% on cruise that the actual AFRs to get close to the estimated AFRs

As you mentioned, adjust the injection multiplier and maps to what you need rather than focus too much on the estiamted AFRs

Yes use the input tracer for sure. If you have your wideband going into Nistune, you can map your AFRs against the RPM/TP. Give it a show to see how it works

Knock monitor is not available for this model. Use knock headphones or a third party monitor. We show some headphones you can build on the main discussion thread

Have a look at our documentation under Support > General documentation on our website for further info
Sofa King
 

Posts: 6
Joined: Thu Aug 08, 2013 5:58 am

Re: General questions about fuel map / tuning

Post by Sofa King »

Thanks Matt.

Ok. So I was right in my assumption that I should just get things right according to wideband, and not to be concerned with Estimated A/F Ratio.

And I tried the input tracer today on the way to work. Pretty cool. Seems like it is more useful for very specific, short pulls though. My drive was ~30 minutes, and it doesn't seem like that's the best scenario to use it, but i'll definitely be messing with it in the future for short pulls.

Cheers!
Matt
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Joined: Sun Jan 29, 2006 1:45 am
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Re: General questions about fuel map / tuning

Post by Matt »

Only if you are recording the long drive and then playing back sections then it would be useful in that case

Also using stream mode (instead of tuner mode) will record more samples
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