DIY EFI System

Buchholz, Steven Steven.Buchholz at
Fri Sep 21 10:29:59 EDT 2001

I know that there has been a reasonable bit of discussion here about CIS not
providing sufficient fuel for engines that have been pumped up a bit.  I
have been subscribed to some e-mail lists under ...
the other day a couple of the more active members of the list announced that
they had produced an electronic fuel injection controller which they were
making available to the public.  This system is pretty much independent of
whatever system is in the car, and has its own pressure transducer ... and
is done in anticipation of super/turbocharging.  I am forwarding the message
below so that those interested can look into it and decide for themselves if
it is worthwhile.  I understand that Bruce will be working to organize a
single group buy/build ... so if you are interested you may want to look
into subbing the EFI332 or DIY-EFI lists at the above link.  I understand
that the system will be printed in an upcoming issue of Circuit Cellar Ink

The thing that most interests me is the fact that Bruce and Al are now
working on a companion spark controller ... one that has circuitry to sample
the ionization in the combustion chamber after the cylinder fires ... pretty
heady stuff for a DIY system ...

I was completely uninvolved with the development of the system, I am just
passing along something that I thought might be of general interest here.
Bruce and Al are pretty adamant DIY'ers (i.e. anti-profiteers) too, I doubt
that they will be making much, if anything on this ... except perhaps
whatever they get from Circuit Cellar Ink ... 

Steve Buchholz
San Jose, CA (USA)
> > All,
> > 
> > For the last several months I and Al Grippo has been working on an
> > inexpensive electronic fuel injection controller for 
> automotive engines
> > whose content is ready for full release to the DIY community:
> > 
> >
> > 
> > Design of this device was undertaken because of the 
> apparent need for an
> > inexpensive, turn-key fuel injection controller by many 
> individuals. The
> > hope was that the EFI332 project would result in a system 
> which could
> > ultimately be used for all applications, and this was one 
> of the main
> > reasons for offering our 4-layer MC86332 board as the 
> EFI332 platform
> > 2-1/2 years ago. However, very few systems have been built 
> and installed
> > on vehicles (Al has been running one on his Camaro for 
> almost 1 year,
> > and Jeff Clarke is ready to fire one up in his restored Corvette). I
> > feel that one of the main reasons for the small amount of 
> operational
> > systems is due to the complexity of the current EFI332 
> system. One has
> > to be both a hardware and software expert, install and 
> learn a bunch of
> > software development tools, write embedded code, and become 
> an expert in
> > engine control algorithms. The EFI332 system is very powerful and
> > flexible, but requires a tremendous learning curve, a wide range of
> > skills, and many hours to pull off. Do not get me wrong - I 
> hope that
> > many EFI332 systems come alive, it is a powerful and 
> complete unit. But,
> > I think that there is another group of people out there who 
> want an EFI
> > system in a more complete and turnkey state, and somewhat simpler.
> > 
> > The philosophy for the MegaSquirt system was simple: provide a
> > controller for fuel injectors which can be adapted to any 
> application,
> > without having to write embedded code or understand the details of
> > engine controls. In addition, provide all the schematics, software,
> > algorithms, etc. to everyone - keep nothing hidden. Provide enough
> > information for anyone to duplicate the system with ease. 
> This is not a
> > commercial unit, but directed to DIY applications. Also, 
> the circuit is
> > going to be featured in an upcoming Circuit Cellar issue.
> > 
> > In short, MegaSquirt is a fuel injector controller (fuel 
> only, no spark
> > control is provided - this is to come later in another system) which
> > uses standard sensors (coolant temp, manifold air temp, throttle
> > position, oxygen, trigger from existing ignition system) to perform
> > batch fuel injector (two banks) pulsewidth control. A flash-based
> > Motorola microprocessor (MC68HC908GP32) is used for the 
> calculation of
> > fuel and injector control. Additionally, host software has been
> > developed (widows-based) which allows the run-time 
> adjustment of control
> > parameters. All information for the system is available on 
> the web site
> > above.
> > 
> > This is not a system under development - MegaSquirt is a complete
> > functional system which has been tested on two applications. I have
> > MegaSquirt installed on my Jaguar (Chevy 350-powered) and 
> is now a daily
> > driver.
> > 
> > --
> > - Bruce
> > 
> > ---------------------------------------------
> >              Bruce A. Bowling
> >          bbowling at
> >
> > ---------------------------------------------

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