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:So here is what I understand:
:1.) The Mass Air Flow Sensor on a Z32 roughly measures the volume of air moving through it based on a known cross sectional area and the velocity of air moving past it.
it's actually measuring oxygen count in Grams per Cubic
Meter. This measurement of oxygen alone is what makes a
MAF car work well in high altitudes and equally as well in
low
:2.) The Air Fuel map of a z32 is a table of values using 2d interpolation of theoretical pusewidth (a value determined by the CAS reading and MAF voltage) and engine RPM.
I think so. AKA "engine load":3.) The stoichimetric ratio of air to fuel is ~ 14.7 lbs of air to every lb of fuel.
Of common "pump" petrochemical gasoline.
Diesel, Alcohol, Methonal, and most(*) race gas all have
unique and varying stoichimetric ratios. This is why the
more scientific "Lambda" is prefered over using the
stoichimetric ratio. I chose the PLX Wideband system soley
for the easily configurable Lambda/Stoichimetric readings,
plus the ability to configure the unit for specific fuels,
eliminating any chance of error.
:The MAF idea conceptually works fine when assuming the air is always the same density; however, in a high altitude environment, the density is much less. I personally live in Albuquerque, NM (~5000ft above sea level), and from what I have calculated, the volumetric density of air is roughly 86% what it is at sea level (calculated from the change of atmospheric pressure). This means that for every x quantity of air that is measured by the MAF sensor (volume), only 0.86x of O2 is actually ingested into the engine.
correct
:Questions:
:So does this technically mean that for the same TP (theoretical pulsewidth) on the Z32 ecu at high altitude I will be running richer than my same setup at lower altitude?
No Or is there some type of correction factor from the O2 sensors which help "teach" the ecu that, for the same volume of air, there is less 02 actually present and will actually lean out all the maps? Or what else am I overlooking?
Yes, the O2 sensors always help, no matter where they
are. However, I firmly believe with most O2 sensored cars
on the road, the ECU/O2 sensor are mearly correcting for
poor maintenance or leaks/timing/plug variables. Ie,
Moving targets. :Additionally, what are the important aspects when tuning for high altitude? Have any of the JWT, Ashspec, Ztuner, etc. ECU users experience different air/fuel ratios than what should be in their maps because of this phenomena??
If I were in Wolf Creek Colorado right now, atop the pass, and tuning a Z... Turbo or NA... my number one concern would be the effective octane count of the fuel being used. I know in most high altitude areas, they use special blends (or atleast a winter blend) of fuel. :This is really confusing me, and I would really appreciate any help.
The big key here is grams of oxygen per cubic meter.
It's like counting rain drops before it hits the ground, so
we know if we need a big mop (more fuel in our case), or a
smaller mop (less fuel).
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