got any idea of what microcontroller is in that box? knowing that, one can start disassembling the BIN.
94 Blazer, Turbo'd 350 TBI - DD
1991 2500 Suburban Adventure truck - 4wd conversion, 4-link F/R, 582ci CNP Big Block with Terminator X EFI backed by a 6L90 and twin stick'd NP205 t-case
2012 Porsche Panamera Turbo - Date night car :)
1979 16' Action Marine/"Johnny Cash" Merc Bridgeport Champ Motor - Metalflake Maniac
pictures/description of the main chip?
after looking at the BIN in a hex editor, it repeats itself right at $8000, so it is actually a 32KB BIN. it has enough vectors at the end of the file to imply to me that it's a standard part, not something like a GM P4 which is its own little brand of different in the world of 6811.
I can look at this more later, I have to leave for a few hours.
28 pin UV style chip that I ripped the bin from just like I would from a 27sf512. ECU is a MAP/RPM only marine unit that is used on high performance 2 stroke V6 outboards. There are multiple variations of this ECU that are the same thing with different chips. The bin I posted is from the most desirable A48 version, which is a 9200 RPM limit. Fueling should be mapped out past 11k (a common mod is upping the rev limit to 11,500 so the high compression drag motors aren't on a limiter at half track)
94 Blazer, Turbo'd 350 TBI - DD
1991 2500 Suburban Adventure truck - 4wd conversion, 4-link F/R, 582ci CNP Big Block with Terminator X EFI backed by a 6L90 and twin stick'd NP205 t-case
2012 Porsche Panamera Turbo - Date night car :)
1979 16' Action Marine/"Johnny Cash" Merc Bridgeport Champ Motor - Metalflake Maniac
preliminary info: standard 6811 from what I can tell. has 256 bytes of RAM. most of the PROM is just completely open... code runs from C379 to D48A, a little more than 4000 bytes. calibration seems to run up to 90BF, at most, even then a lot of it looks like filler.
I imagined it would be, but have no clue what to look for. Not sure if I mentioned it, but the powerhead this was on was 2.5L and has vacuum referenced fuel pressure (up to 39PSI at WOT) Besides the MAP sensor, they have a Temp sensor directly on the head, not sure how it is utilized by the ecm though. I'm interested to get this to the point of tuning, with 250lbs of compression and 112 Sunoco a remap of the fuel curve would be huge.
Would the actual injector flow rates help in any way? I have a set of injectors that have been cleaned up and flowed, I can post the numbers tonight if it would help.
94 Blazer, Turbo'd 350 TBI - DD
1991 2500 Suburban Adventure truck - 4wd conversion, 4-link F/R, 582ci CNP Big Block with Terminator X EFI backed by a 6L90 and twin stick'd NP205 t-case
2012 Porsche Panamera Turbo - Date night car :)
1979 16' Action Marine/"Johnny Cash" Merc Bridgeport Champ Motor - Metalflake Maniac
any information would certainly help. if there were any kind of datastream specifications or a rough idea of where the various signals making it into the 6811 go(though with all of that epoxy, I can't see much being easily discerned), that would be helpful too. as-is, I'm guessing at quite a bit at what exactly I'm looking at. going through the power-on reset routine now, nearly at the section where all of the RAM has its values initialized to 0. doesn't look like anything is "learned", though with a marine application, unless it has automatic idle adjustments, not much would need to be. after the RAM is cleared, it does seem to initialize quite a few values to some rough values in batches. it also reclears some values for no apparent reason?
I haven't found any type of checksum function yet. after the initial powerup stuff i'll take a look around for 2D and 3D lookups, should shed some light on some unknown stuff.
89 K1500 Scottsdale 5.7L 5spd 3:42 RamJet cam Dart iron TBI heads 427 PCM swap
95 C2500 Cheyenne 6.5L turbo diesel 4L80e 4:10 DB2-4911 Manual pump conversion 0411 PCM trans control 2Bar COS
05 Outback XT 2.5L turbo gas auto
i couldn't tell if that was a hex switch or a trim pot.... either could have some effect on fuel/spark, but I'm not nearly far enough into the code to say for certain.
can almost make out the crystal frequency from that pic, but not quite.... that information would be good to figure out some of these timing calcs.
Map sensor. Everything is internal to these, the tygon tube exits the aluminum case through a rubber sealed opening and attaches to the Plenum.
The trim pot will adjust the whole fuel curve plus or minus 10% from the base table. When you go higher compression or cut the intake to get more air in the motor, the only way you can adjust them is by richening up the entire curve until it's not lean when wide open... which is fine at WOT but tends to make the motor slobbery at part throttle and idle.
Here's the injector cleaning sheet. They were tested at 56PSI and the numbers listed are cc/min.
94 Blazer, Turbo'd 350 TBI - DD
1991 2500 Suburban Adventure truck - 4wd conversion, 4-link F/R, 582ci CNP Big Block with Terminator X EFI backed by a 6L90 and twin stick'd NP205 t-case
2012 Porsche Panamera Turbo - Date night car :)
1979 16' Action Marine/"Johnny Cash" Merc Bridgeport Champ Motor - Metalflake Maniac
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