Tuning available for 93-95 L32 and L82 PCMs

[madtuner]

This post is not meant as advertising. I just wanted to shares some news with the V6 community and ask for help from local members.

Mostly as a side project, I have been working over the past few months on developing software to tune the neglected 93-95 L32 and L82 PCMs (service numbers: 16172693, 16184737 and 16196397). If anyone local is interested in helping me to continue develop the software and offer more parameter tweaking, I would greatly appreciate it. My software reads and flashes over the diagnostic port, so no disassembly or physical changes will be done to your car. I would need the car for a few hours, perhaps during several different days. As part of the process your PCM will also be updated to the latest GM calibration available and you will of course receive free tuning and diagnostics if you like.

I can adjust quite a few things at the moment, but a few parameters such as adjustments for gear ratio changes are still not fully implemented.

I am located in DeKalb, IL. You can contact me directly at support@madtuner.com for more details. Thank you.

[95cutlassproject]

I hope that you do mange to fully crack into the PCM. I know a few of my friends would greatly appreicate being able to get there car tuned.

[pocket-rocket]

I really hope you can fully crack it as well. I have no use of it, but it would be nice to stop having to tell people to revert to full OBD1 or upgrade to full OBD2 and allow them to use their current hardware

[robertisaar]

interesting..... i'm sure i could expand on the stuff you have decoded already, but Dekalb is a bit far away for me...

[madtuner]

Robert,

I take it you have modified your tune already at some point? Please let me know which parameters you have been able to uncover. I've got enough to tune most cars out there, but I am still missing a few parameters for more advanced modifications.

I have used your datalog definitions in the past by the way. Thanks.

[robertisaar]

i've never messed with the OBD1.5 native code, i've been too busy adding stuff to the $A1 mask.

i've never came across(nor had the ability to write) the software required to actually write the tune to the PCM, which has been my big hangup.... pulling it via the ALDL circuit is cake though.

if you could send a few BINs my way, i could probably run them through my disassembler though, just need to know which areas to focus on.

[madtuner]

OK Robert, maybe we can combine efforts and add features quicker since I have so many other projects.

Please e-mail me at support@madtuner.com and I will send you a few bins. I have developed my own software from scratch, though I am curious what you mean by pulling it through the ALDL circuit.

[robertisaar]

you can dump BINs through the ALDL circuit, same way the 94-95 LT1 guys do... couple different methods to go about it actually, i believe mode 2 commands typically are fastest without sending a custom program over the ALDL that resides in memory and just continuously dumps the BINs(since there are 2 32KB PROMs to deal with).

don't suppose you have interest in the 93-95 NorthStar stuff as well?

[madtuner]

Interesting. I never even bothered to try that. I just wrote my own bootloader. Could have saved me a little bit of work. Will reply shortly.

[robertisaar]

considering mode 2 sends a total of 6 bytes(including checksum), and then recieves 64 bytes of RAM or ROM in a 68 byte packet(checksum included again), it's a fairly efficient and simple method. just have to increment the address by 64 bytes for every command until you get to the end of the PROM. since these PCMs use dul 32KB PROMs, it requires a total of 512 commands to grab all of the bytes from 1 PROM. takes about ~55 seconds per PROM IIRC.

[95cutlassproject]

So many great things seem to be happening. We have the nAst1 progject, the custom intake(superchargers anyone) and now the possiblity of tunable obd 1.5 PCM this is going to be amazing!

[19Cutlass94]

This could be interesting! Although a little late for me, as I already swapped to OBD1

[tkoforpresident]

This could be interesting! Although a little late for me, as I already swapped to OBD1

x2 lol

[madtuner]

I am glad to see there is some interest in this. I just had a few of these PCMs on my shelf for nearly a decade and finally decided to give them some TLC. As I mentioned before, I have already developed the software to fully read, upload, some datalogging (though this can be accomplished via Tunerpro already thanks to Robert's definitions) and I have mapped out quite a bit of code and variables. I expect to be able to tune them for any modifications in a couple of months with a little bit of help.

[robertisaar]

man, are you guys in for some surprises.... i've never seen/played with an OBD1 PCM other than the northstar PCM that uses some 16 bit 3D tables.....

i've never seen a 255 row 2D table until now either.

another interesting tidbit: it almost looks like GM left in the code to use a PCS equipped transmission in the FWD cars. not sure if the hardware is there though.

i'll shut up and get back to hacking now.