Ford vs GM in the ECM wars.

[Frederic Breitwieser]

>Why is the GM ecm preferred over the Ford eec-iv?  I have a ford I would
>like to convert to EFI someday.  I do have better documentation on the GM

In General, the Ford ECM does some neat, adaptive things the GM setup can't
do, however the GM has one major advantage - the PROM that contains the
code, data, and other good stuff can be ripped out easily and replaced.

The Ford unit is soldered to the system board :(

Also, not that its all that important, the EEC IV (Ford) is intel based,
where as the GM units (at least up until around 1990/1991ish) are Motorola
based.

Other than that, they are different methods of arriving at the same goal.

Most factory engine management systems are fairly conservative to keep in
line with the federally mandated vehicle emissions and miles per gallon
requirement...

For example, my 1993 Lincoln, which uses the Ford EEC IV computer, does
very well with 6-7 lbs of boost from the installed supercharger I crammed
into the engine compartment.  Aside from risking detonation, I'd think any
more boost than that might be out of the scope of the EEC's ability to "get
a grip" on the environment, as the airflow would exceed what its programmed
to "expect".  Radical cams, higher compression, larger injectors (and the
list goes on) introduces different variables in which the computer, at
least in its OEM/factory state, would not be expecting.

An excellent resource would be ISBN 0-87938-743-2, "Fuel Injection -
Installation, Performance Tuning, Modifications" by Jeff Hartman.  Its
available from Motorbooks International at 800-826-6600 for about twenty
bucks if I remember correctly.  My cover's a bit worn so the price is
pretty much missing.  I've read this book cover to cover several times, and
use it as a resource quite often.  

Before I read it I only "had a clue" how EFI really works, now I have a
slightly "bigger clue" <Grin>


Frederic Breitwieser
Homebrew Automotive Mailing List
Bridgeport, CT 06606
http://www.geocities.com/MotorCity/Downs/4605/index.html
(Portable Webserver Link Address)

1989 AG Hummer 4-Door
1993 Supercharged Lincoln Continental
2000 Mid-Engine Sports Car <smile>

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