Seen this yet?

[jdbubb at ix.netcom.com (Dan Bubb)]

Fueling is determined by a load vs. RPM matrix.
Load can be determined by a MAF (mass airflow meter), TPS (throttle position sensor) or MAP
(manifold absolute pressure).
Megasquirt generally uses a MAP sensor for load.
So, at each of the 64 matrix locations in the standard 8 x 8 matrix you would enter an engine VE
(volumetric efficiency) and that number would correspond to an injector open time. You can put in
any value you want, good or bad.
The AFR table lets you put in a target AFR for each of the 64 positions. The Megasquirt will then
try to correct the VE value to obtain the AFR that you want irrespective of the correctness of the
VE entry.
If your VE entries are very close to actual requirement then the auto correction to the desired AFR
will be minimal and the power/economy benefits will be minimal. If the VE entries are way off the
unit will correct and you should see a benefit. I'm sure there is also a way to see what the
corrections are and write them back to the VE table.
HTH.
Dan


----- Original Message -----
From: "David Utley" <fahrvegnugen@cox.net>
To: "Dan Bubb" <jdbubb@ix.netcom.com>; <scirocco-l@scirocco.org>
Sent: Wednesday, July 14, 2004 5:06 PM
Subject: Re: Seen this yet?


>
> >
> > From: "Dan Bubb" <jdbubb@ix.netcom.com>
> > Date: 2004/07/14 Wed PM 01:12:37 EDT
> > To: <scirocco-l@scirocco.org>
> > Subject: Seen this yet?
> >
> >
> > Not exactly new news, but this stuff justs keeps getting better.  12x12 table, ignition
included,
> > target AFR,
> >
> >
> > http://www.megasquirt.info/ms2/
> >
> >
> > Target AFR! Not too many aftermarket management systems have that!
> > My 16V is crying out to me!
> >
> > Dan
>
> Target AFR, so you can target an air fuel ratio, and MS will go to that, regardless of any other
input?  I am a little confused.  IF I am on the right track, can you adjust what AFR you want for a
given RPM, and perhaps load (although I am sketchy on how it would discover the load)?
>
> I am interested, just fairly computer illiterate, esp. with MAF-type EFI...
>
> Cheers,
>  David
>
>
> ---Chrome don't get you home.---
>