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Discussion Starter · #1 ·
I recently purchased a 95 RMS and I need a base tune to check the shift points for the trans. The previous owner thought the PCM was bad and replaced it, but it has a Roady Wagon tune in it and I am pretty sure that the gears in the wagon with 2.93's I have 2.56's in this car so I just want to be sure. Also with the new Tunercat or the updated version when you change the tire size and differential it should change the affected transmission values, correct. I am just curious I tweaked the original file that I had from my 9C1 as far as trans shift points, but it has a 3.08 gear in it, so I am assuming that these would be off a bit or different anyway. Also I had to replace the original trans with a newer one that I had which is a 96, is there any specifications as far as line pressure, etc. that would be different in a 96 trans? Thanks for the help.
 

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I can get the file for you wheni get home tonight. As far as the differences between the transmisisons, there are resistance values that are different with the newer transmissions that translate into different commanded shift times and certain thresholds. I have cheat sheet somewhere that explaines it better. I'll try to find that and send it to you as well. If your used to tweeking stuff, your probably on the right track. Make small changes.

Chris
 

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Discussion Starter · #3 ·
Thanks man I appreciate it, I wouldn't say that I am used to tweaking stuff, just playing with stuff little by little to change things, As far as the 96 trans I had a copy of the tune that my buddy had in his 96 imp, which was a performance tune from back in the day, I looked at the tables in his tune in relation to the tune I downloaded from the PCM in my car and changed line pressures and offsets according to the way his was tuned, but I didn't change any of the shift points as I knew they would be different as he had 3.73's in his car. I could send you the tune that I have right now if you are bored to see if you think that I am on the right track. :)
 

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Well, i had a roadmaster folder in tunercat or so i thought. If you know what the broadcast code is, here is a short list of the publicly available broadcast code bin files.

ftp://ftp.diy-efi.org/pub/gmecm/bin_lib/16188051/

I have a couple more places to check.

Chris

*edit* I think the BMDZ EE.bin on that page is what your after
 

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Discussion Starter · #7 ·
Well I am having no luck, I looked at a 94 fleetwood tune and it was different, but I was guessing that it had 2.56's in it. So what I need is the shift tables from any car that is out there that has a 2.56 in it, any help please, something is off, as it is shifting too early from what I can tell.
 

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Well I am having no luck, I looked at a 94 fleetwood tune and it was different, but I was guessing that it had 2.56's in it. So what I need is the shift tables from any car that is out there that has a 2.56 in it, any help please, something is off, as it is shifting too early from what I can tell.

I have my tune at home somewhere. will be a few horus before I'm home.
 

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Both the Sedan's, and wagons had 2.56 standard. Both had 2.93's with the towing package. The shift points for RPM should not be effected. My 2.56 Roadmaster and 2.93 Roadmaster oth shifted great when I swapped PCM's between the two cars, and also with a PCM from a 9C1.

If matt doesn't get you a tune, I have a file of all the PCM's I had laying around. I don't think I actually have a 100% stock 2.56 Roadamster tune. I had Matt adjust the shift points slightly, years ago.
 

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Discussion Starter · #13 ·
Yeah Matt got me the tune from his car, OEM anyway, and 95Wagon sent me one as well. The wagon that the pcm came from must of had 2.93's in it, the shift points are different between the two, quite a bit actually. IT was mainly the chugging around town shift points that were off, it seemed to shift very early for my liking, I will probably still tweak it a bit, but I have to drive it first. It needs an alignment, but I think that the front springs were torched to lower it, not sure, but it sits a little lower in the front and unless the kid that had the car smacked something hard on the right front, you can tell this with the alignment, the front tires are pointing away from each other. I will tweak it to get it to the shop I go to, but we will see.
 
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