That is true and an absolute!
mr.prick is right. read through this thread from the front to the back, I think it will really help you and its free.
It is very good stuff and it helped me.
98 tigershark
14.07, and we need to discuss spark and timing now!!!
The newer PCMs say 14.07.
Ha Ha HA, You got mr.prick to stay on this thread. I am glad as he always stays on course!! I mean that as a compliment too. But that is a very good question also because it is more than just the E%. When are we going to get around to the Spark aand Timing issues too and what that does to the AFR with the E fuels and the vaporization issues and spark and flash. No mater what the E fuel% is, the motor seems to pick its spot as far as timing regardless of what is commanded, and timing does affect how the actual AFR is obtained also, Since that is static, something is tricking the PCM, How can this be and how do we adjust spark for the correct AFR in B3601? My logging says it is right today(new gas from Portland), but, I put an old fashioned timing light on the HB and it says it is different than the PCM is commanding this weekend. I had that happen before and it is not a loss reluctor. Is the PCM is commanding the right timing or just showing it that way when I log. In other words do the E fuels trick the PCM as that is all I can think of as that has to change the commanded AFR also??? Really!
98 tigershark
Quote:
Originally Posted by
mr.prick
I do understand so get this.....
I set up my car making it think it had larger injectors by about 6%. You would think since B3601 is static that the IBPWs should be smaller and the AFR way off. Under the PE/RPM table the IBPWs were more, they should have been less and run lean. The PE AFR was the almost the same and the commanded Tuned/Logged timing logged a higher than actual when checked with a timing light on the HB. I am switching to LAMBDA for the most part and did not get this finished as planned. But this I know, The PCM does seem to be able to be tricked. I have no clue how this happens as the trims were almost the same. In 97-98 Vette PCMs are set up to run rich stock @62psi Inj pressure so I would buy your theory for those years but that was changed to a leaner condition from 99 on @58 psi and Inj flow accordingly.
Go Figure,
98 tigershark
Quote:
Originally Posted by
Chalky
I am aware of this. My point being did GM set the PE table up as unusually rich or were they acknowledging the fact that many cars would see E10 and set up PE tables to acknowledge a rich non-ethanol AFR or a damn close PE for E10.
