FW: MAF Upgrad

[jb24 at chrysler.com]

I don't know about GM MAFs, but Bosch MAFs sense flow only in a portion
of the body.  That is, the same sensor is used for many different flow
capacities, just different bore diameters.  The ECM is only reading
frequency, that is RELATIVE flow, which you should be compensating for
with fuel pressure and injector size anyhow.  I know some aftermarket
ECM suppliers make huge MAF bodies.

John Bucknell is jb24 at chrysler.com
---------------------- Forwarded by John R Bucknell/JTE/Chrysler on
02/24/98 12:40 PM ---------------------------

        owner-diy_efi @ efi332.eng.ohio-state.edu
        02/24/98 12:31 PM
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Subject: Re: FW: MAF Upgrad

>case.  It might be easier to just have one MAF supply voltage (and the
>other is a dummy) and just change your tables to compensate.  i.e.
assume
>that twice the amount of air is entering the engine as the MAF says
there is.

The advantages of doing this is its very simple to devise - bolt on a
few
MAFs and connect them up.  But, with my desire to run twin turbo's, this
introduces more potential for problems, as I'd have to have the ECM be
aware of one turbo is boosting higher than the other...  I debated for a
while, physically mounting the turbo's in such a way that I could put a
shaft rod between them to ensure they boost at the same level, but I
dunno.
 I started making my manifold anyway, though the front of the intake log
plenum has an open face - I'll be welding on a panel with either one
hole
or two depending on how I'm going - I have two MAFs, two ThrottleBodies,
and using two, allows more flow with cheap OEM junkyard parts.


Frederic Breitwieser
Bridgeport, CT 06606
http://www.xephic.dynip.com/

1993 Supercharged Lincoln Continental
1989 4-Door Softtop Humvee (Hummer)
2000 Buick GTP (Mid-engine track car)

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