Default MAF sensor curve

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Fred
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Default MAF sensor curve

Post by Fred »

This is a fairly meaningless thing that will need to be setup per installation anyway, but I thought I'd post what I am going to do for others to see regardless. Because it doesn't really matter there probably isn't much point in discussing my exact chosen default, but the thread is here, so post your thoughts if you have any on the subject. No 20 questions though ;-)

MAF lookup value = (((ADC/16)+3.5)*0.39)^3.3919

Which produces a nice curve from close to zero through to close to 65535 max unsigned short value.

Fred.
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shameem
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Re: Default MAF sensor curve

Post by shameem »

I was just looking into this over at MS land - so here's the link

http://www.microsquirt.info/mafmap.htm

Usual disclaimer - you may have to copy/paste link in new window/tab for it to work....

EDIT: it actually works - lets see how long though...
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Fred
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Re: Default MAF sensor curve

Post by Fred »

It may have worked because you already had the paged loaded (cached, so didn't pull a fresh copy, just displayed what you had already).

Certainly, it's broken now :-) Which isn't necessarily a bad thing, I don't need any of their info anyway.

Pretty hacky way of doing things IMO. Check out their AlphaN "algorithm" too. They translate TPS to fake MAP via a 6x6 table, bizarre.

Having said that, second rate stuff like MAF and TPS control don't deserve quite as much effort as MAP does so I might implement a few hacks of my own. Or, I might do it properly from the start. Not sure yet.

Fred.
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
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