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QLCC History


Here is some history behind the QLCC ECU chip mods that RDH started on
the MAC-02 ur-Quattro back in the Fall of 1995. RDH has a web page with
more details on the MAC-02 code he developed. Go to
http://www.tiac.net/users/rdh/http/ for more info.

Many people on the qlist were discussing ECU mods and raising the boost
on the Audis, people began looking inside their stock and modified ECU's
and discussed which tuner did this, and which tuner did that, resistor
mods, fuel pump hard wiring, zener diode mods etc. were discussed. Paul
Timmerman of Schrapnel Knobbin fame was also involved in these
discussions about raising the boost on the Audi ur-Quattros and on the

RDH posted some detailed information on the manifold pressure map values
from the MAC-02 ECU code on Dec. 12th 1995 which caught my eye. Dave
Lawson had been in contact with RDH during this same period and knew RDH
from a previous meeting. RDH developed the software code that would
dis-assemble the EPROM code Hexidecimal values from the MAC-02 ECU and
match these against the MAC-02 micro-processor (uP) instruction codes 
or operation codes (op codes).

The EPROM in the ECU contains both data and the actual instructions in a
Hexidecimal format (base 16). The actual uP instructions are used to
monitor the engine parameters and then set the timing and fuel
(frequency valve duty cycle), monitor engine component operation and
issue fault codes etc. RDH spent many hours, (days/months?) reverse
engineering the data (Maps) portion of the code along with the actual uP
instructions. RDH sent me the disassembled listing he had for the MAC-02
code around May 10, 1995 and after doing a quick look and comparison to
the MAC11 ECU code (1986-88 5000TQ), I was able to locate the regular
and premium timing maps in the MAC11 code. The Audi Factory Service
"1986 new Model information" that I had, shows the MAC11 timing map
graph, so finding the timing map values was pretty easy. The timing map
values are the first 32 lines of the code in the EPROM and this is where
the MAC-02 had its timing map as well. 

I posted a note the quattro list indicating that I located this timing
info.  Dave Lawson had also been working on the MAC11 code previously
and after seeing my post to the qlist, indicated he had also noticed the
timing maps and had some other suggestions for some of the other code
locations. Steve Eiche became interested at this same time and had been
doing some of his own investigation, Graydon, Scott J. and others became
intersted in the code findings as well. On 5/28/96 I announced to the
qlist that I found the overboost fuel pump cutout map. I did this by
graphically comparing the MAC11 code to the MAC-02 code which also used
this overboost fuel pump cutout feature.

Now it was possible to change the overboost cutout map values and allow
running boost above the stock 1.6 bar cutout value,using the stock ECU
pressure sensor this overboost cutout could be set up to ~1.95 bar
before the fuel pump cut out would occur.

During this same time, RDH had sent me the software code for doing the
actual disassembly of the MAC-02 code and I believe Dave Lawson had also
begun working with RDH's code to run on his PC. (Dave Lawson, please add
any details or corrections where needed). With RDH's help and patience,
I was able to get this program to run on my Unix mainframe at work.
Unfortunately, not being a software programmer by trade (Electrical
engineering is my bag), I was unable to make much progress modify RDH's
program to correctly work with the MAC11 code and accomplish the
disassembly process. 

At some point, (Orin help me here) I believe that I sent a copy of RDH's
program to Orin up in the Seattle area and this is where the real
progress began on the MAC11 code. Orin modified the RDH program and
began reverse engineering the MAC11 code. Orin located the actual "boost
maps" that the ECU uses along with the Waste Gate Solenoid to
dynamically adjust the boost above what the Waste Gate Spring pressure
can provide. 

During this time, I provided some Audi technical information which
helped Orin and others with the deciphering process and I also started
doing some on car testing to understand how the map values corresponded
with actual engine parameters. Other people on the qlist got involved at
the same time and were doing there own work on the code as more and more
information became available. 

The important thing to note, is that this information was freely spread
between 5-6 people who were investigating how the MAC11 ECU worked and
had the hardware or software knowledge to futher this investigation.
Dave Lawson worked with Scott J. on correlating the K26 Turbo
characteristics and investigated the disassembled listing of the MAC11
code to come up with a modified version of the  MAC-ll to work well with
this K26 output profile. I was working on the later MAC14 code
modifications at the same time to make my 1989 200TQ with the dual knock
sensor engine run better and better. I believe Dave Lawsons version of
the MAC11 code was spread out amongst several other QLCC list members
who agreed to do some low cost EPROM upgrades, Steve Eiche, Dave Lawson,
Graydon Stuckey, David Kavanaugh, Steve Buchholz are a few of the people
who began offering this service as well as the service I was providing
using my own version of code. In some cases each person made changes to
the QLCC code as they did more testing. (If I left anyone off this list,
please correct me)

The QLCC name "Quattro List Chip Club" I believe was coined by Steve
Buchholz after I jokingly suggested we put together some sort of chip
club like the "Hair club for Men"

Well, after going through my notes and old email posts that I have, that
is how I remember this QLCC thing happening. Other thoughts, with
additions or corrections are most welcomed from other members in this

Happy code crunching!
Scott Mo.
1989 200TQ