'97 pcm in a '00 obs 2500

[Hezsus]

The 350 from the 97 would bold right up, im assuming you want the manual trans over any automatic, which i would probably do too. whatever you do you are looking at a tune, and for the extra cost of a 411 you can get one of those tuned.. I know if you get lucky bbperformance sometimes has them in stock, or they will tune your 2000 pcm for you as well. or lots of other people tune, i got mine done on my stock 98 computer by juston @ blackbear and now wish i would have gone with the 411. but either way it sounds like a good project.

 

[Aloicious]

Thats kinda what I was thinking, I could always load a 5.7 liter manual transmission base tune on the 411 or even the 00 pcm and go from there, even though the automatic stuff is still plugged into the pcm. it would ignore the automatic part wouldn't it?

yeah if you load the manual trans tune than it would be correctly setup, if you have efilive or something, it'd be easy to flash it correctly. if not, a mail order tune from someone would be sufficient for a stock or near-stock setup on the engine.

trying to run it with a manual trans and automatic tune may cause issues, among getting alot of 'where the hell is your transmission' codes, you might have some kind of limp mode going on, as well as probably some other issues.

 

[Blue975speed]

yeah if you load the manual trans tune than it would be correctly setup, if you have efilive or something, it'd be easy to flash it correctly. if not, a mail order tune from someone would be sufficient for a stock or near-stock setup on the engine.

trying to run it with a manual trans and automatic tune may cause issues, among getting alot of 'where the hell is your transmission' codes, you might have some kind of limp mode going on, as well as probably some other issues.

I figured on that, the pcm is gonna get flashed with a factory manual tune, i know the tech at a local dealership who would come out and flash it with the tech 2. A problem I may run into is having to use the running in park/neutral mode. The problem is the VSS doesn't work in park/neutral does it?

I was planning on swapping in the manual, using the electronic np243 t case (unheard of, I know), and only wiring in the backup light switch. I don't need the clutch cruise kill switch nor the clutch start option. Doing just those things I'm hoping the truck doesn't abort mission on me. I'm not looking to go too wild and crazy tune wise right now, just as far as having it on close to factory without the TM.

 

[Aloicious]

I figured on that, the pcm is gonna get flashed with a factory manual tune, i know the tech at a local dealership who would come out and flash it with the tech 2. A problem I may run into is having to use the running in park/neutral mode. The problem is the VSS doesn't work in park/neutral does it?

I was planning on swapping in the manual, using the electronic np243 t case (unheard of, I know), and only wiring in the backup light switch. I don't need the clutch cruise kill switch nor the clutch start option. Doing just those things I'm hoping the truck doesn't abort mission on me. I'm not looking to go too wild and crazy tune wise right now, just as far as having it on close to factory without the TM.

you mean like when you're coasting in neutral? the VSS works all the time, the VSS is just a reluctor wheel with a sensor, so as long as the shaft is turning, you'll be getting a VSS signal (it will always be turning when you're in motion, regardless of P/N or in gear)...The issue you may have with the VSS is that different transmissions use different reluctor wheels, so you may need to re-calibrate the PCM to read the VSS signal correctly....for example, the 4L60e uses a 40 tooth reluctor (40 pulses per revolution at the VSS)....but when I swapped in my T56, it uses a 17 tooth reluctor (17 pulses per revolution)...the PCM is calibrated to send the correct signal to your speedometer from these pulses, (i.e. X amount of pulses per mile based on the reluctor teeth, gear ratio, and tire size...this is why a re-tune is needed after a tire size or gear ratio change to correct the speedometer), so if the trans/Tcase setup you're going to be using is different than what is in the PCM, your speedo will be incorrect. hopefully the tune your buddy can re-flash in there will be correct, or at least alterable (I'm not too familiar with how much the tech2 can customize a tune, but I would think it could handle a speedometer calibration change).

 

[Blue975speed]

I was just reading the VSS thing, they said that the VSS isn't active or something when the truck is in neutral park mode for the Auto, for the truck to start with the manual it would have to be in neutral park mode, but beings the VSS is active anything the shaft is in motion that checks one more thing off my list. The Tech 2 can't really play with the tunes much but it can load a factory tune and play with the speedometer, later on I was planning on Blackbear or something similar.

Though, I have been trying to learn about how to start tuning. I want to learn how to read the fuel charts and such but I have no idea. This is just for incase i decide to do a little head work and maybe swap a little hotter cam in later on down the line. All that I know is that you want to tune conservative so that you don't wash the rings of oil.

 

[Aloicious]

yeah, with an automatic you have to be in park to start the truck, but on a manual they're talking about the neutral safety switch on the clutch pedal assembly, its just a switch that interrupts the starter wiring, so that the starter doesn't get power unless the clutch pedal is depressed, you can bypass it if you like, it has nothing to do with the PCM or VSS though. if the tech 2 can correct the speedometer, than you will probably be okay even if the VSS reluctor is different, thats the main problem the VSS might have...

Tuning is fun, there is a sharp learning curve, but once you get the hang of what does what, its not too bad. if you ever get to the point where you want to start tuning I can help you out...in fact sometime in the near future I want to start a series of articles over on my site about how to start tuning, and more advanced topics like how to tune various parameters.

 

[Blue975speed]

Thank you all much for your help, I may have some other questions for you down the line. I'm thinking of spliting my hard drive on my mac loading windows 7 so I can then load EFI live and do some logging and tuning. I'm actually going to take a class in december that is like the introduction to EFI tuning, just gives you the basics. I hope it will give me some of the limits i can go to, If it doesn't then I guess thats what internet forums are for lol.

I'll be sure and post my progress when it all gets underway, right now I have some cab work and some body work to do before i go through all this pain.

 

[Aloicious]

no prob.

'eh the class won't talk about specifics much because they'll change from vehicle to vehicle (especially fueling and VE tables, though they'll probably talk about wideband O2 sensors to correct VE tables), its probably a good class to take to get a handle on the physics of the engine and how the PCM controls it through sensor inputs...etc...I can help you get efilive hardware when that time comes if you want...the software is free though, so you can download it and some tunes and kinda see how things work in the PCM...