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U500 with Unicat camper
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Discussion Starter · #1 ·
My (formerly) EGR equipped 902.912 (OM906LA family) has timing 14 deg BTDC. Euro 3 906s of similar vintage (906.955) are 18 deg BTDC. I have ECU modified by a seemingly knowledgeable turbo service in eastern Quebec. Supposedly 18 deg BTDC and 290 hp.
Anyone have any actual experience with timing changes on OM906LA with regards to fuel consumption?
I have pyrometer installed.
The corresponding Euro 3 engine is 906.955 (279-286 hp, 902.912 rated at 260). Maybe I should have purchased 906.955 ECU, but the injectors probably have different part #s and I wasn’t sure about them communicating.
My current ECU works fine, but I’d like a 2-5% decrease in consumption if possible.
I am trying to obtain bsfc graphs for both engine versions.
 

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U1450L DOKA
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12,496 Posts
Best of luck with your quest. I can guarantee you that I will be of no help here whatsoever.
My Engine is dumb as a stump, and I can just keep up with it.
Strong as an OX, and twice as smart....
Happy Thanksgiving !
 

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'91 U1250 '02 U500NA
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The engine in my U500 is 906.967. It is last year before EGR.
Here is the list of injectors to fit this setup:
A 002 010 25 51
A 004 017 65 21
A 005 017 77 21
A 006 017 22 21
0 432 191 278 BOSCH
 

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U500 with Unicat camper
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949 Posts
Discussion Starter · #4 ·
What I essentially need to know: given same engine in all respects (902.912), what happens to consumption when advancing injection timing 4 degrees; from 14 to 18 deg BTDC? The majority of 906s are set at 18 BTDC.
 

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U1450L DOKA
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That last one - at least the torque curve is a little flatter above 1700 RPM.
The previous two charts …. Once you hit 1600-1700
RPM the torque falls off a cliff.
Any idea where to find similar charts for the OM352’s
And OM366’s ?
If they have similar characteristics, if you get
Stuck and want to pull yourself out of it, then
‘Standing on it’ would look to be counterproductive.
 

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U500 with Unicat camper
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Discussion Starter · #9 ·
You can see both the standard and M03 consumption curves bottom out at 195gm/kwh.
Knowing the minimum bsfc figure for the NA version (missing, also in my source) would essentially answer my question. AFAIK, 4 deg timing is the difference.
 

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U1450L DOKA
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Of course, I looked in the Data book and the horsepower and torque charts for the OM352 are all there - NA, Turbo, Turbo / Intercooled, with the Max torque called out at the optimal RPM.
 
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