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When's MAFT switch between base and WOT?

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Old Mar 17, 2004 | 11:34 AM
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Default When's MAFT switch between base and WOT?

Few questions about MAFT (sorry search didn't help):

1) Does anybody now exactly when MAFT (v.4.0) switches between base and WOT settings? I assume that happens when the reading from MAF reaches a certain constant (g/s)?

2) When MAFT thinks you are at WOT (and makes WOT corrections), are the base corrections neglected or not? I.e. if the base=+5%, and WOT=+2%, would the actual correction to MAF reading at WOT be +7% or +2% ?

3) Some people wrote certain tuning procedures for MAFT. They claim that base settings relate to cells 1-19 and wot - 22. Obviously MAFT has no way of knowing which cell the engine is using as it doesn't know readings from other sensors, and so I can only accurately tune for one cell [aside from #22]. Can anybody confirm that and elaborate on what cells would be best to use for max power (i.e. when you roll off the line at 2-4k rpm but are not WOT yet)? Currently I have some hesitation at ~3krpm - it appears when I reach about 3-4krpm, the car jumps slightly like a turbo car when turbo spools up. I'd like to make power delivery smooth, if possible. Thank you
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Old Mar 19, 2004 | 02:01 PM
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Nobody knows? People from ramchargers perhaps? They still sell it... except people have little idea of how it actually works... Please, share
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Old Mar 19, 2004 | 03:03 PM
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A web document I have sez 8kHz transition,
or roughly 70-75% of full scale mass airflow.
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Old Mar 19, 2004 | 09:01 PM
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Originally Posted by jimmyblue
A web document I have sez 8kHz transition,
or roughly 70-75% of full scale mass airflow.
Can you post a link?? Is the WOT operation affected by base setting? Thanks.
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Old Mar 20, 2004 | 07:13 AM
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I got it off vetteguru.com, way back; looks like it's at

http://www.vetteguru.com/mods/maf/

Some mention there about abrupt / "jerky" behavior due to
poor supply decoupling on older models, as well.

also

http://www.ramchargers.com/RamNews/T...tor_manual.htm

for the basics.

What I see sez the base setting is a straight scaling on
frequency across the full range, with the WOT kicking in,
higher, as another "adder" to that (though the exact
math is a bit unclear, the base is said to be applied
always).
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Old Mar 20, 2004 | 11:24 AM
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Thank you. That is definitely useful.


Originally Posted by jimmyblue
I got it off vetteguru.com, way back; looks like it's at

http://www.vetteguru.com/mods/maf/

Some mention there about abrupt / "jerky" behavior due to
poor supply decoupling on older models, as well.

also

http://www.ramchargers.com/RamNews/T...tor_manual.htm

for the basics.

What I see sez the base setting is a straight scaling on
frequency across the full range, with the WOT kicking in,
higher, as another "adder" to that (though the exact
math is a bit unclear, the base is said to be applied
always).
Reply




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