Delco 16220371 ECU (Mercruiser 502 magnum MPI) EEprom

[Espen Hilde]

>  A friend of mine is prepairing for a dyno run in a superflow bench.
>  The engine is a Mercruiser Magnum 502 MPI  1996model.The engine is
equipped
>  with a procharger kit.
>  Thats a sentrifugal compressor  with a water to air intercooler, the
only
>  change to fuel/ingition is a rising rate
>  fuel pressure regulator.The compressor is giving a modest 5 psi
boost.The
>  boost starts  from 3000rpm.
>  We are going to strap the engine to the dyno with headers and have then
>  access to exhaust temp for 
>  each  cyl.   We can borrow a scan tool from mercruiser  (price 1000
usd.) ,
>  but we want a scan tool that can be used for cars and other
engines,maybe
>  for a better price.Diacom?
>  It would be nice to have access to the ecu , so we can alter the maps
for
>  ignition and fuel under boost.
>  Is it anyone who have info about this DELCO ECU? There are several
numbers
>  attached to the ecu box:
>       16220371
>       Modell                860371ka00002699                    White tag
>  :9456
>  The box is just 13,5cm  times  10cm
>  One multipoint connector on each side  , 32 pins each
>  One connector in the wier harness to connect to the scantool : 10 pins
and
>  6 is used. 
>  The efi system is MPI with MAP  and knock sensor. No ego .   Map sensor
is
>  :039-5160
>  injectors:5467(difficult to see)  Ignition system is mercruiser HEI 
with a
>  distributor.
>  It would be nice if this ecu was the same as a much used car ecu.
>  We need advice on what equipment we need to be able to alter this ecu.

AND how to do it!.......

>  Type of prom?
>  E-prom burner?
>  Eraser?
>  Software?
>  scantool?
>  realtime modulator?
>  Any input /ideas is appreciated 
>  Thanks 
>  Espen Hilde  
>  
>  Hi Espen,
>       The Mercury Marine computer has a 512 byte EEprom(not 512k)...
The box is not possible to open, since it is a EEprom, is it possible to
alter code without removing the chip?Or do we have to dig it out to read
it?Is the pinouts on the side direct to the EE prom?Is using EEproms usual
in car ecus?I tought just aftermarket efi systems used it.How 
where you able to read the 512k...sorry  to bother with these details , I
got to have it by a small spoon.  

what I
> haven't been able to figure out is whether this is a compressed format or
if
> 512 bytes is all they need since it is open loop and has very little
control
> over the engine....the only cool feature I have seen on it is if it sees
> enough knock not only does it remove timing it also enriches the fuel to
cool
> the chamber(about 1 air fuel ratio). As for the scanner...I have a couple
of
> new ones for $400.(US) with the 99 updates.  Rhinda(Diacom) makes the
scanner
> for Mercury and they do offer a laptop version as well but can't remember
what
> I paid for it.  From what I have seen the centrifugal setup you were
talking
> about doesn't handle the fuel enrichment very well and hurts idle quality
and
> part throttle cruising because of correcting the mixture by increasing
the
> fuel pressure at all times then boost compensating above that.....let me
know

if this code in the ecu is very special , it is maybe difficult to use a 2
bar MAP sensor,and calibrate for it.
Maybe we have to stick with low boost and adjust at wot where we know the
boost is.

> what you see,,,I am interested......AZ Speed & Marine does have the
capacity
> to alter the calibration in the ECU......I haven't spent much time
looking at
> the 512 byte file but think I figured out the rev limit and how to adjust
how
> much fuel enrichment when the knock circuit is hit hard...but thats about
> it.....That processor does not do double bar fuel or timing,,,,

Double bar fuel and timing......whats that,what is the bennefits?

but the new 99
> controller does,,,,bad thing is the 99 has a revolving checksum location 

what is a checksum needed for ?

so
> has been really tough to even get started with.....as far as I know 
unless
> you're GM or have some "backdoor" avenue to get the software, there isn't
any
> to be had,,,,,but again if you find some I am interested......btw the
checksum
> for your 512 is the 9496 on the outside of your ECU on that white
tag...Anyway
> hope that helps.

Helped a lot , thanks  Carl
Espen Hilde