simple code request for maf

Testing and development of Megasquirt 3

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ashford
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simple code request for maf

Post by ashford »

can we get map for the load axis on the trim table? switching fuel load under general to speed density switches algorithm to speed density as well.

when tuning the trim table making a change in a cell moves the actual used cell around creating a "chicken or the egg" scenario. for example a maf with a bit of a resonance( i will exaggerate a bit for clarity) at 3000rpm and 100% load(no boost) if that bin is changed from 100 to 120 fuel load is now 120% and using that bin instead of the 100. this causes some goofy behaviour if there are peaks or valleys in the trim table. for example if you are in boost a little and it is rich at the same rpm lets say 120 kpa worth of boost so you pull 20 % in the 120 load so it has 80 in it it will now report 100 load and use the 100%in the ve table
subwoofer
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Re: simple code request for maf

Post by subwoofer »

You should be able to do this already, but it will not be called "trim". Bare with me if I don't call functions by the correct name, working from memory.

Disable the trim table, enable secondary fueling table (VE2) as speed-density, multiply, don't multiply MAP. Fill VE2 with all 100s and start tuning.

Or did I misunderstand the problem?
Joachim
1974 Jensen-Healey
1990 VW Caravelle Syncro - running MS3+X
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jsmcortina
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Re: simple code request for maf

Post by jsmcortina »

I don't understand the question. The trim table should not be altering "Load", if it does then it may be a bug.

Please attach an MSQ and describe your test scenario. (A datalog might not help.)

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ashford
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Re: simple code request for maf

Post by ashford »

it initially appeared like changing maf trim table around changed load as i was getting an unrealistic high maf load, i was seeing 200% in boost of about 130 kpa to meet target afr. trim table was aveaged around 160% with about 20% added to the maf transfer. when tuning light throttle areas it seemed to push the load around while tuning, this may have just been an ilusion

the car has holley 120# injectors, with a versafueler as the peak and hold driver, dual 450 lph pumps on 2 ford fpdms, e98 fuel (9.0 stoich mixture)

initially i was set up with a numerically correct required fuel for injector size and fuel type( 5.4ms) and maf transfer from the manufacturer. later on i increased the required fuel to 7.9(@50%) then multiplied the trim talble by .7 and ended up with numbers near 100 in boost and i am still reading in excess of 200% fuel load, so it appears the trim table isn't affecting fuel load but the numbers still don't seem to be adding up it takes roughtly 11-12 ms to reach target afr at 200% load with a req fuel of 7.9 and trim table near 100. perhaps something to do with 1300gs maf selection?

being able to select map as load axis for fuel load would still be helpful, i remember now it can be done mostly like subwoofer said( completely forgot about doing it the old way).

here is the newest msq and log from the last tuning sesion. the car is not mine but i will probably see it again as i told him i don't like the way the maf is physically setup and should have an intercooler installed also.
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