Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
CM2250 VGT delete issue
#8
the MCF "Mass Charge Flow" manager is the manager responsible for converting intake pressure and flow requests and sending then onward to the VG turbo manager(s).

Someone can make special procedure and calculations all they want to and adjust on the MCF tables but it will not effect a mechanically driven turbo or how the egine runs. Simply disable any derates it wants to impose because it can no longer control the "air" and leave it alone.

(study carefully what I say here if you are someone still learning, this is the correct info) ...
===============
The MCF is fed by the CBR/CBO (combustion request and off nominal correction request managers) and is selected by what engine mode your in, etc... it then gets sent to => and filtered by the CHL (charge/boost limit) manager then goes thru the => CSE (charge/boost system error correction) manager then goes thru the => CSE-Xform angle manager so it can be split into offsets for clean vs. dirty air / intake pressure requests and EGR requests, then goes onwards to => the TGC control manager (turbo geometry control) and is converted to positioning requests then goes to either the Air controller for a CM 870 or for electronic turbos, out to the TAHR filter (turbo anti hysterisis (anti-chuff) filter) then onwards to => the VGT (vg turbine manager) and the VGA (vg actuator control manager) and finally out to the J1939 controller sending messages to the turbo.
============

That is the chain of command for the MCF. Some1 can tweak on it till their face turns purple, and all they gonna see is messages changing on the J1939 for a turbo that is no longer connected to it and errors if they get it too far out of whack that can simply be set on ignore just like like cummns does when they use an HX series.


The fuel-air mix, injection timing, torque curve, and any sensors that were removed need to be re-adjusted properly. It does take doing things right, and making some comprimises on the bottom end fuel-air-mix because the BW is a bit lazy on the bottom end if it is cpec'd with he right exhaust housing for a 15-litlre. Turbo inlet temp sensor needs override and set to roughly 125 to 130-F (thereabouts) for correct combustion offsets if its been removed. isx neds to see a tiny bit of heat at that sensor to estimate turbo heat soak, its finicky that way, so if some1 removed it, it needs to be set. A borg-weener turbo does not match the respomnse curve of the isx. Because of this, if it has the right housing for the `1500+ rpm ranges needed for isx, the bottom is lazy and fuel-air-mix needs to be set to allow a bit of extra fuel (bordering on making black smoke when some1 stomps accel pedal) on the bottom end to get it spooled up quickly, otherwise the whole engine is a bit laggy. But in no way should it take some special fancy-talked BS software.

fuel milage is going to go to the dogs vs. healthy engine and vgt. save 5k on turbo to spend 8k or more a year on fuel losses, depends on what truck used for tho. . gotta love it.

U also loose most of the engine brake. just make sure it dont over-boost at high rpm too. for a 2250 that would be about 35-37 psi max before detonation sets in and starts fretting mid-stops. a wastegate added to one is your friend cuz u can use the smaller housing and make it spool up faster on the bottom end and let the waste-gate blow off the excess above 35 psi or so when it gets goin.

should mention too that in about 2 or 3 years, sound like some1 gonna be crying they lost the enigne due to garbage can tuning and poor-man decisions. thats the road it sound like its on anyhow.
My intention is only for to be helpful on here on occasion and noting more. What I post is always grounded on a factual basis, as I have no tolerance for ppl who try to use fakery, fancy-talk, etc. to try to impress others.
[-] The following 6 users say Thank You to MaraJin for this post:
  • colterHD, dawn patrol, DewDewMax, harobaua, littlet666, schISM
  


Messages In This Thread
CM2250 VGT delete issue - by colterHD - 05-28-2020, 04:13 PM
RE: CM2250 VGT delete issue - by moon monkey - 05-29-2020, 06:56 PM
RE: CM2250 VGT delete issue - by colterHD - 05-30-2020, 10:31 AM
RE: CM2250 VGT delete issue - by zyNoT - 05-31-2020, 04:53 PM
RE: CM2250 VGT delete issue - by colterHD - 05-31-2020, 05:40 PM
RE: CM2250 VGT delete issue - by zyNoT - 05-31-2020, 07:19 PM
RE: CM2250 VGT delete issue - by colterHD - 05-31-2020, 07:53 PM
RE: CM2250 VGT delete issue - by MaraJin - 06-04-2020, 12:13 AM
RE: CM2250 VGT delete issue - by colterHD - 06-04-2020, 11:19 AM

Forum Jump:


Users browsing this thread:
5 Guest(s)