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bodiesel
January 25th, 2019, 09:58 AM
Newbie, but got her to run today with help from this forum.
Thought this lesson learned was worth sharing :

In addition to tweaking the pedal and torque curves to modestly increase torque, I raised the hard ( 4000 ) and soft rev limits ( 3800 ) , torque, pedal, and timing tables to support 3800 RPM. At first the ECM still limited me to 3200 RPM but bounced harder off the limit (hmm, seems the increased torque parameters were working) . Then I stumbled upon another setting. It is a setting that only shows up with V7.5 running, tune selected, and plugged into my truck, key in run position. It presents at the bottom of the "Internal Flash" list and is titled " Operation Monitor ". it's parameter ID is F8812 or {F8812} . I had to set it to disabled , save the tune, then reload with V8 to allow revs over 3200. It is now a dream to drive shifting gears at 3500 RPM and not yet on the rev limiter .

GMPX
January 25th, 2019, 10:04 AM
That F8812 parameter is used to control a complex algorithm in the background that monitors the RPM, Fuelling etc. It is sort of like a co-pilot to the main mapping just making sure the final fuelling, torque calculation don't end up at something way out of range. Rather than try to massage those numbers to suit changes tuners just wanted to be able to disable it. I have a feeling some of the factory calibrations may have had it turned off too.

2007 5.9
January 25th, 2019, 12:06 PM
What ecm are you using?

bodiesel
January 26th, 2019, 02:49 AM
what ecm are you using?

2350b