*NEW* Duramax Injection Timing Calculator

[Braden_P_F]

I have been working on a new injection timing calculator for a while now. It's easier to follow than some of the older ones floating around. The spreadsheets calculate the actual injector pulse width that is being used based on your injection pressure, injection duration and injection BTDC (%) based on your current timing. Currently, the spreadsheet calculates timing for the following Duramax:
LB7 & LLY
LBZ & LMM
LML
L5P

I will add others once I can get my hands on some stock files.

EDIT: v1.0.2 - fixed a couple mistakes with L5P calculator
EDIT: v1.0.3 - fixed missing column on LBZ fuel pressure table
EDIT: v1.1.1 - fixed problem with LLY-LBZ tables

[Junkrunner]

Looks very nice. Only problem is that on my lbz the pulsewidth table uses kpa instead of mpa. When I paste the data in it causes err:502 in the calculated pulsewidth table below it. Am i doing something wrong?
Looks like you did a lot of work on this. Thank you for freely sharing.

[Braden_P_F]

The units can be changed simply by right-clicking on the table in HPT, I chose Mpa as it is much simpler to have 2 or 3 digits instead of 5 to 6. I also cannot replicate your error, I looked up that error. It has something to do with an invalid argument. Are you copying your entire pulsewidth table into the spreadsheet?

[Junkrunner]

I think the problem was that my base pressure table had an extra column in it and it pushed the data past the end of the table in the spreadsheet. I modified that and it seems to work ok now. thank you.

[Silvergs72]

Your missing the 95 column in the fuel pressure table

[Braden_P_F]

Thankyou for pointing that out, I added the missing column to v1.0.3

[SUTTERERMAN85]

Thank you for sharing this with us!

[Silvergs72]

One quick question on this is do you use the new data in the default timing table and then use the difference in all the other timing tables?

[Braden_P_F]

One quick question on this is do you use the new data in the default timing table and then use the difference in all the other timing tables?

Yes, kinda. As altitude goes up, the timing needs to be advanced. I usually advance the mid alt by 1-2 degrees, and the high alt by another 1-2 degrees. Or you could use the calculator and increase the percentage BTDC by a little bit for mid and high alt maps.

[rs6]

Can new L5P injectors be programmed with MPVI 2+ and VCM? My ECM is unlocked and tuned already. I've got some water damaged injectors and need to program the iq codes into a new set.

[J.Dial]

Timing Calculations are close, but there are some errors. Checked against my LBZ Timing Calc:
ss.png

The multiple lines of FORECAST matching are difficult to audit, I use macros to do bicubic interpolation, but the forum won't allow macro enabled xls uploads, but it is much easier.. my Injection Duration cells are simple: =0.000006*$B71*BicubicInterpolation(pw_table,C$70, BicubicInterpolation(fp_table,C$70,$B71))

The L5P Used Pulsewidth looks quite a bit different when using bicubic interpolation as well:
L5P.png

You can find the macros at https://mathformeremortals.wordpress.com