Does the MAF reading look normal here on dyno (pic)
10-27-2005, 01:17 PM
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Does the MAF reading look normal here on dyno (pic) I just noticed this after about 12dyno runs, never really paid attention to the MAF values on the Chart display on HPtuners.
On this one I ran about 26* timing and it took it all the way to where I cut off. On that one it made about 414whp.
But looking at the MAF on the chart it looks like the rocky mountains, why does it fluctuate that much and is that normal? Because if I follow the histogram on the spark table, its bouncing around from anywhere between .60 g/cyl and .84 g/cyl.
Dixit
On this one I ran about 26* timing and it took it all the way to where I cut off. On that one it made about 414whp.
But looking at the MAF on the chart it looks like the rocky mountains, why does it fluctuate that much and is that normal? Because if I follow the histogram on the spark table, its bouncing around from anywhere between .60 g/cyl and .84 g/cyl.
Dixit
10-27-2005, 01:27 PM
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The MAF output has some noise to it (frequency,
sampled can have some "interesting" artifacts
even if other electrical noise is not contributing;
Helm manual indicates that ignition noise can be
a significant interferer). I believe this is one reason
why there is so much "massaging" done to produce
the "dynamic airflow" value from raw MAF, and
DynAir is used instead by the fuel computation.
sampled can have some "interesting" artifacts
even if other electrical noise is not contributing;
Helm manual indicates that ignition noise can be
a significant interferer). I believe this is one reason
why there is so much "massaging" done to produce
the "dynamic airflow" value from raw MAF, and
DynAir is used instead by the fuel computation.
10-27-2005, 01:35 PM
#3
yup, it's normal. if you wanna try something though, log a bunch of maf freq vs maf sae, and just graph it as a bunch of xy tuples. then clean your airfilter and do the same log, and the raw data log will be way less noisy. it's pretty awesome to see how not cleaning your filter throws off your maf readings.
10-27-2005, 01:54 PM
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Ok thats what I needed to know. I got a feeling that with the dips in the MAF reading that I see I sometimes see it knock out of nowhere like 2-4* sometimes. So that may be part of it. But for now 26* WOT timing looking good and no problems.
Dixit
Dixit
