Basic GM TBI injection questions.

[mfwic]

I just joined this group also. And I have similar questions about the fuel
maps used.

We want to use an existing fuel map as a starting point for a digital
controller that we are
building as part of a graduate student project. We have a target vehicle
and some preliminary
electronics.

The vehicle has a 350SBC with a throttle body from the Chevy dealer and a
Holley
Pro-Jection brain from the flea market. It has a turbo from a Buick
Grand National along with a new cam for the turbo. We want to replace the
Holley brain 
with a digital controller of our design.

We have watched most of the signals and we are starting to collect
real-time data via
a 68HC11 evaluation board(EVB) and a laptop running Labview.
The EVB will probably not remain as part of the final design but is easy to
use at this stage.
We also have a Motorola DSP 56K EVB and a PIC BASIC Stamp that will be part
of the initial development.

We want to modify the fuel map with a neural network.(this is the actual
graduate student project). Any
suggestions for the neural network would be appreciated but what we need to
know at this point concerns
the PROM's.

Where can we get info on what data is located where in a PROM ?
How many inputs/outputs in the look-up table(s)/map(s)?
We have the capability to read/program any PROM up to 28-pins.
We have been reading what we can find on GM controllers but haven't found
very
much specific information.

Any help or direction would be greatly appreciated.

Rich Klinger
Cone-shaped hat with oak-leaf clusters

----------
> From: Carl Summers <InTech at writeme.com>
> To: diy_efi at efi332.eng.ohio-state.edu
> Subject: Re: Basic GM TBI injection questions.
> Date: Monday, March 09, 1998 6:30 PM
> 
> Mike Dillon wrote:
> > 
> > I just subscribed to the group and looking for some referances on
> > GM TBI injection systems. The particular one I am working with
> > is from a 89 caprice with a 350 engine. The plan is to give it a new
> > home under the hood of an 83 Jeep Wagoneer (The big one) with a 360
> > AMC engine. I can work out all the mechanical problems without to
> > much difficulty, but I would like to be able to retune the ecm's
> > PROM based on learning mode base table offsets.
> >  I am hoping that someone on this group can fill answer some
> > basic questions about the ecm and proms.
> > 1) What processor does GM use in there ecm ? I looked at my ecm and
> >    all the chips were labled with Delco numbers (No help to me)
> > 2) Does the PROM carry both the control software as well as the
> >    calibration data ?
> > 3) I see referances to 747, 730 ... is one better than the other(s) ?
> >    does one have more functionality than the other(s) ?
> > 4) Has someone other than a few companys broke the PROM code ?
> > 
> > Thanks Mike
> > 
> Hi Mike,
>     The computer you are looking at should be a 1227747 and takes a
> 2732a chip....but if you used the one from the caprice it has air temp
> correction the 747 has not,,,,not that it's that big a deal but air temp
> correction is all about smog and yes the 747 has only lookup tables and
> not very much code....but finding the fuel table shoudn't be so
> difficult to modify......let me know if you need help.....and the code
> isn't always in the chip................c-ya
> -Carl Summers