ZPaul2Fresh8

Hello all!

Anyhow, Man I'm getting tired of removing the damn PCM everytime I want to tune my 93 Z28. And with speed density, I assure you I've removed that damn PCM about a hundred times pin pointing the VE and Spark tables

I've heard of something for us Chip guys to Flash program our chips without removing them, but don't want to spend the money on that. And since everyone is on the OBD-I conversion train, I figured I could get an OBD-II PCM cheap. And I have a complete OBD-II wiring harness.

Anyone see any problems with doing this? Here are somethings I'm taking into consideration, feel free to bring up any points

1. No MAF, but I can run Speed Density.
2. Intake manifold. 94+ Have the fuel cross-over tube, this might be a neccesity with having sequential injection.
3. Software. TunerCAT is suppose to be releasing OBD-II Def Files

That's all I can think of at the moment and at this point the pros out weigh the cons and I'm close to doing it, I just wanted to know what everyone thought.

96TurboTA

TunerCat has been "just about to release" the OBDII stuff for 2 or 3 years now.

badblackta

I to have thought about doing this. Nice to have Lt1 edit so you done have to remove the computer. However, you arel osing part of the tunability of having a obd 2 computer, by not have the 4l60-e, so you cant adjust your shift points and stuff like you could on a 94 and up car, unless you bit the bullet and bought a 4l60-e. might want to up the injectors while your at it also. I was about to do the swap, then decided to just get my own chip burning set up so that I could do everything myself. If you wanna try it, I say go for it. Let me know the results if you do.

LWillmann

I think you'll have to convert the timing set or something to add the crank position sensor.

You'll have to have a different knock sensor (100k ohm instead of the one you have now).

You might have to change fuel rails

If you want it to run in closed loop, you'll need a MAF

Since you're not running the e-version of the tranny (4L60E), you'd probably need a PCM or at least a tune from a manual car, but I'm not sure.

ZPaul2Fresh8

96TurboTA: I just talked to TC today. They will be releasing their OBD-II version TC and Def Files in 2 weeks!

badblackta: I don't care about shift points, I shift manually at the track and my shift points are adjusted manually at the throttle body And injectors would not matter much in this case since my 93 came with 24#...oh I have 30# SVOs in anyhow.

LWillmann: I haven't gotten much into it, but I know the car won't run with out a CS working. I'm sure there is some way to bypass that. Maybe with the new TC. The car ill run in closed looped with no MAF.

Again, this is all just a thought. The only reason is to tune easier since I'm a tuning nut! Ah well, just something I thought I'd throw out there. I'll let you guys know what happens.

badblackta

well last time I checked 93s had 22 lb injectors but those 30 lb svos will definitely get the job done

Injuneer

It will run fine without the crank position sensor.... it is only used for misfire detection in OBD-II. The data the PCM needs for crank/cam position comes from the Opti, just like it does in your 93. You just have to eliminate the CKP from the PCM.

As far as I know, the PCM will enter closed loop without the MAF functioning.... can't think of any reason it would be necessary to avoid closed loop without the MAF. "speed-density" is simply another way to measure mass air flow.

96TurboTA

It's about time

ZPaul2Fresh8

Well I used to believe 93s came with 22#ers, but out of the 3 93s I've tuned, they all were calibrated from the factory with 24#ers. So I tend to believe myself more than some people on this board

sleepy_z28

If you decide you're going to do this and need an OBDII PCM, I got one out of a 96 Z28 I'd sell. Drop me an email if you're interested............RFRIGR8@hotmail.com

sherwinZ28

They told me it was going to be released in 30 days.
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that was ~ 1 year ago.