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View Full Version : LMM-Turbo Vane Target Position



killerbee
January 19th, 2010, 11:59 AM
os 594, There are 6 or 8 of these tables. I noticed that some of these have a different vertical scale than others. Is this intentional? All go from 0-120 fuel, but they are graduated differently.

GMPX
January 19th, 2010, 01:06 PM
This is the scaling in the tune, not sure why GM chose those breakpoints, they changed again in the LMM from memory.

husker_diesel
January 19th, 2010, 01:07 PM
which table are you talking about specifically?

killerbee
January 19th, 2010, 01:26 PM
B2210-B2215

B2215 has a lone wolf vertical scale, different from the rest.

GMPX
January 19th, 2010, 01:47 PM
ok, now I know the one you mean. I don't have an answer as to why GM (Bosch) chose to make this table different to all the others doing a similar function. But the table size is defined in the calibrations as 16x16, not the normal 23x23.

Cheers,
Ross

killerbee
January 19th, 2010, 03:28 PM
While on this topic, I am having a real struggle with boost. From what I can assess, I am getting a vane position command, not a boost command. I can depress the pedal, and vane will rise, and stay right at, say 50%. No modulation, flat line. I would expect the vane pos to be all over the place working the boost set point, and that is not happening. The boost will rise, slowly, in response.

The end result is high boost, and eq ratio sometimes below 0.6 on accelerations. That's clear cut overboost for tuning purposes.

Any ideas? B2231 and B2232 do not appear to be in play here.

killerbee
January 19th, 2010, 03:43 PM
Shows what i am talking about. Constant vane ops, as opposed to constant boost.

http://forum.efilive.com/attachment.php?attachmentid=7039&d=1263955360

bballer182
January 19th, 2010, 04:47 PM
I see you have found a suitable "number" for the EQ ratio for the lbz/lmm. did you use the first half of my equation and dial in the "number" to obtain the correct eq ratio?

killerbee
January 19th, 2010, 04:54 PM
Honestly, IIRC, I am using the same equation from earlier gen. The original equation.

It is really entertaining to watch it when the EGR kicks open. Watching MAF drop by 70% is a hoot.

duramaximizer
January 19th, 2010, 05:03 PM
Ya and you can feel the power loss, a real hoot.

bballer182
January 20th, 2010, 03:19 AM
Honestly, IIRC, I am using the same equation from earlier gen. The original equation.

It is really entertaining to watch it when the EGR kicks open. Watching MAF drop by 70% is a hoot.

If you don't mind could i get the fudge number from you?

killerbee
January 20th, 2010, 04:06 AM
PM sent

duramaximizer
January 22nd, 2010, 07:48 PM
Could I get this number and an explanation of what you are trying to do. I think calculate mathmatical efficiency?

rcr1978
January 23rd, 2010, 06:31 AM
I would like to know also