Rkreigh

I've always wondered why the GM folks have been so slow to adopt wide band o2s for the factory computers.

A long time ago I was working with a tuning wizard Bob Bailey who did all kinds of tricks with the buick ecm to add features to the base operating system.

I know this would be a monumental effort but is it possible to update the base operating system to reference a wide band and do tuning adjustments?

in lieu of that, would it be possible to "comment out" the secondary injectors from being controlled by the ECM and let another stand alone computer control them independently (like the Linc system Graham did on the LPE TT cars).

I'm looking to get a discussion going on some options in case santa brings me some turbos <G>

jss06c6

Struggling with this as well. I've got the WB installed and have analog out ready to log, but can't seem to get the WB O2 data packaged with the ALDL data stream.

Box I bought has the ability, but I have yet to be successful with it.

ajrothm

Jon will figure that out for you...no problem...

jss06c6

We've been discussing it. Not an easy solution since the A/D channels aren't comingled with the ALDL data stream. This provision is there when communicating via the Moate's APU1 but can't get communication going in this mode. Even has the Moate's tech support guy (who has been very helpful) at a blank as well. I have to try to get my ADX (data stream definition file) written to communicate through the APU1 and the ALDL cable to the ECM..

Dominic Sorresso

Todd Pepmeier has done the integration of a WB w the stock ECM. I believe he decided against continuing w it due to the slower frame rate of the stock ECM v the WB itself.

tpepmeie

There are a couple ways to answer Ron's question, depending on what he means. Just logging the WB analog output to a free A/D channel in the factory program is easy. Then you can include that channel in the ALDL stream, add it to your datalogging definition, and log it along side all the other variables.

Or, a long time ago, I actually had the car running closed loop lambda control using the wideband O2 sensors. This required major modifications to the code, to use the 0-5v signal rather than 0-1v NB signal. And if I recall, lots of work on the PID variables to reduce the corrections (rather than force large swings in the NB sensor voltage). I never had the courage to leave it in CL during Power Enrichment, although that could have been done.

In the end, it was just an experiment, and I went back to the philosophy that is get the fueling right with the separate WB controller, then remove the WB and run it Open Loop. I was actually running the 427 closed loop with stock NB feedback, but the wild cam overlap made for poor idle fuel control. Above idle, the stock logic worked fine.

Dominic Sorresso

Whenever you modify the motor, u end up needing to "massage" the Prop Gains to tame the idle in particular. That's assuming you idle in C/L.

ajrothm

Damn... That sounds terribly complicated and scientific...especially for tuning a 27 year old car....lol

I'm not well versed in ZR1/C4 tuning methods at all...but I know my buddies with Grand Nationals now have a computer chip that is flashable like a late model PCM, you plug your laptop right into the chip in the pcm and write to it as needed..You can even datalog from the chip.. I think the device is called a Power Logger.--You would think there would be something similar available for the C4 pcms.

Good luck on your mission, I'm QUITE sure you and Jon will get it figured out.

Sux you guys didnt get to make it to Sulfer Springs.

jss06c6

Alan,

We were both bummed we couldn't make it. Actually I could have made the run, but didn't want to without Jon. We will be there next year!!

I've got a solid tuning system now, thanks to the help of a lot of great forum members (Corvette forum and ZR1 net registry!) Will install new O2 sensors early next week and re-log BLM Data to tune VE tables, then move to WOT tuning with wideband.

Steve