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Questions about tuning using HPtuner

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Old Oct 31, 2004 | 08:09 PM
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Default Questions about tuning using HPtuner

Hi,

I just got my HPtuner for my 99 vette and had some questions. I scaned my car and the LTFT values vary in each box, do I use the average, max or min for the readings and also the o2 readings. Also I changed the IFR table to adjust for the 28 injectors that replaced the stock 26. Can I do another scan right away or should I wait for the computer to learn the new IFR tables. Thanks and any advice is appreciated.
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Old Oct 31, 2004 | 08:34 PM
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Originally Posted by cbota
Hi,

I just got my HPtuner for my 99 vette and had some questions. I scaned my car and the LTFT values vary in each box, do I use the average, max or min for the readings and also the o2 readings. Also I changed the IFR table to adjust for the 28 injectors that replaced the stock 26. Can I do another scan right away or should I wait for the computer to learn the new IFR tables. Thanks and any advice is appreciated.
No need to wait for a change on the IFR table.. there is not really a "learn" per say with that change they are pretty linear.

The general consensus on the LTFT tables is to average values in cells 6-14 and make sure they are between -3 and -8 for the average. I would shoot closer to the mean rather than the -3... try for -5, my suggestion only.

Don't worry about using the stock O2 readings for tuning, they are not a very good way to tune for WOT and are worthless at part throttle. I am assuming you have done some other mods to the car, not just changed injectors?
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Old Oct 31, 2004 | 08:49 PM
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Originally Posted by GEN3Typhoon
No need to wait for a change on the IFR table.. there is not really a "learn" per say with that change they are pretty linear.

The general consensus on the LTFT tables is to average values in cells 6-14 and make sure they are between -3 and -8 for the average. I would shoot closer to the mean rather than the -3... try for -5, my suggestion only.

Don't worry about using the stock O2 readings for tuning, they are not a very good way to tune for WOT and are worthless at part throttle. I am assuming you have done some other mods to the car, not just changed injectors?
Yes, all the mods are listed at the bottom of the post. I was on a dyno and my AFR was 11.5 at wot, so I am just tring to raise that alittle and wanted to see if the o2 are of any help. Thanks for the info
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Old Oct 31, 2004 | 09:02 PM
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Yes, you should let the ltft's learn for a while so you can see the results of your ifr changes.
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