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Making changes to VE table, NOT in SD mode???

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Old 10-06-2005, 11:49 PM
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Default Making changes to VE table, NOT in SD mode???

Is that bad??? I have a big cruise this weekend, and don't have time to reset everything. Can I make changes not in SD mode? Will it hurt my previous tuning?

Thanks,
Jaosn
Old 10-07-2005, 12:24 AM
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you'll have to make adjustments to the maf tables i would imagine. Since theory has it that the ve is referenced by the maf when it is being used. Im sure someone else will chime in. You ready to race Ed?? get it on video too You know Ed and his "proof"
Nino
Old 10-07-2005, 01:24 AM
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Its not referenced by the maf. Its used as the primary fueling table though on throttle transients and is blended w/ the maf fueling at <4000rpm i think.
Old 10-07-2005, 07:31 AM
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wait...what???
Old 10-07-2005, 08:18 AM
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Don't have time to reset everything? It takes 2 minutes to copy hi spark to low, disable ltft's, dfco, maf and maf mils. Then, log the stft's vs. map vs. rpm and adust ve accordingly. Worst case scenario, you have to go back to your current tune if you don't get it closer by the cruise. Just make sure you don't overwrite/delete it. Besides, you could run speed density to the cruise. It won't hurt if your ve is close enough.
Old 10-07-2005, 09:15 AM
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Originally Posted by SSpdDmon
Don't have time to reset everything? It takes 2 minutes to copy hi spark to low, disable ltft's, dfco, maf and maf mils. Then, log the stft's vs. map vs. rpm and adust ve accordingly. Worst case scenario, you have to go back to your current tune if you don't get it closer by the cruise. Just make sure you don't overwrite/delete it. Besides, you could run speed density to the cruise. It won't hurt if your ve is close enough.

I was talking about the LTFT's. If I change something, don't I have to reset them? So, I gather from you said, I should just log STFT's and not LTFT's?

Jason
Old 10-07-2005, 09:17 AM
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when did you mention ltft's?? your gonna reset them after your done adjusting what you want. Drive around on the freeway for about 20-30 minutes today, then on the way to the cruise, your ltft's should be learned does that help??
Old 10-07-2005, 09:17 AM
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Originally Posted by ninobrn99
you'll have to make adjustments to the maf tables i would imagine. Since theory has it that the ve is referenced by the maf when it is being used. Im sure someone else will chime in. You ready to race Ed?? get it on video too You know Ed and his "proof"
Nino

I am SOOOOO ready for Ed.

I even have my own way of getting proof.


We'll see if I can hang with all that HP.
Old 10-07-2005, 10:02 AM
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Originally Posted by ninobrn99
when did you mention ltft's?? your gonna reset them after your done adjusting what you want. Drive around on the freeway for about 20-30 minutes today, then on the way to the cruise, your ltft's should be learned does that help??

What I really meant...If I log today(not in SD mode), and make changes to the VE ie:LTFT and STFT. Will that be ok? Or is it a must to be in SD mode to make changes to the tables?
Old 10-07-2005, 11:39 AM
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I never took my MAF offline although my fiddling
was not that hardcore (still stock cam / intake /
heads and only minor exhaust improvement).

Most of your idle and low cruise airflow is SD basis
and your low-RPM trims are mostly about the VE
table. If you think the MAF is trustworthy then
you can just change the VE table column that
represents idle, by your Cell 0 LTFT value (like
if LTFT=-10, multiply by (1+(-10/100)) or 0.90.
The 1200 column, see how the trims taper from
Cell 0 to Cell1 and take a wet-thumb guess at
a proper scaling by interpolation; for 400 you
have to extrapolate some.

Then see where the trims settle to, and take
another crack at it if you fell short or overshot.

Bearing in mind that your trimming can be bent by
O2 sensor degradation or lack of heat, and that
the MAF does start to contribute to the airflow
product as RPMs rise (meaning that VE changes
will not result in a 1:1 LTFT movement like they
do at idle), and that some vehicles "bundle too
much range" in the LTFT trim cells making the
trim not always about, what you think it's about.




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