Trying to get 6 cyl Fiero with DIS running properly on 7730 ECM with S_AUJP but having problems determining proper spark settings. Anyone know the correct values?

DIS is running with these but not best:
70 deg ($c7) Address 0x025 Initial Spark Advance (Base Distributor)
0 deg ($0000) Address 0x026 Max ADVANCE Relative to SA-REF
-60 deg ($ff55) Address 0x028 Max RETARD Relative to SA-REF

Thanks, Elky

 

They are close enough that it should work:

https://www.thirdgen.org/forums/v6/5...ml#post4436973

RBob.

 

Thanks RBob. Wow, so much conflicting info in that thread which is what I've run into after hours of searching. Why is there not a one stop place for such info, or does one exist and I just missed it? With the 6 cyl Chevy using DIS, seems the numbers should be published or available somewhere. What mask/bin did the v6 with DIS use?

To the matter at hand. Simulating the $8d spark calculation at idle with 850 idle RPM =Commanded Idle RPM at temp so there are no adjustments to spark calculation, I get the following:



Initial setting just does not seem right. Way too much REF spark, right?
Changed seems better but still a lot of REF spark to ECM. Which is correct?
Why is SA-TDC less than SA-REF?
Is the difference between TDC and meaningful?
Is the Base setting same as the Reference Angle?

Apologies for all the questions, but really trying to understand this for other than 8 cylinders!
Thanks, Elky

 

Masks $A1, $8F, and $31 are set up for DIS. But note that $A1 and $8F handle these values differently.

RBob.

 

Thanks again RBob! But when time permits, would really appreciate your pondering the other questions.
Elky