ISX CM2350 VGT & Brake Table

[Moose]

Thank you for that answer.
It's a 2350 common rail.

The jake table is going to get returned to stock values.

Now after a de-mandate in a prior truck (CM871) I saw an immediate 1MPG gain just by the HC Doser injector not using anymore fuel. Further work & tuning yielded about a 1.5MPG total gain.

This CM2350 with the same de-mandate I'm losing about a MPG since. Something is not right. Some of the red flags of a crappy file are evident, but some things are dead on; Boost tops out at 35psi, shaft speeds are less than 120k under full throttle. Exhaust temps max out at 1100F at the k-probe pre-turbo and 1200F calculated. The turbo just seems like it trying to work entirely too hard and the fuel mileage is agreeing. I've got 5psi @ idle with 40k shaft speed 82% VGT, 10PSI at light throttle and then it drops off over 1100rpm. I want to fix this. I've got too much money and time in rebuilding this one. I don't want redneck tuning... I want it not to breathe it's own soot and last beyond 400k miles.

I'll pay more attention to the MCF and operating mode. Plus I can go back and look at the other cals now that I know what to look for. When you say that "stock cals for common rails are rich as hell in the idle regions and need to be compensated for" Does this vary from cal to cal, family to family? What i've learned even back in my days working for this maker is that they were poor idling engines and needed some load to smooth out but excessive idle load, if not for aftertreatment heating purposes, was compensating for a bad running condition or in this instance maybe, a piss poor tune?

But, If I cannot get this rectified, a stock engine with better fuel economy is going to be better than what I have now. I could have lived with a lateral move but a loss in mileage I cannot. I know it can do better...

Thanks again