small pulse adjust {B4005}

fuel/injectors/small pulse adjust

this table is (Msec, Msec),

therefor how does this table respond to larger injectors for example 60 Lbs siemens.

do the values increase or decrease from the stock values.

the one example that Ive seem, has this table with no proportionality to stock.

I would have thought that the larger injector requires more energy to turn on, and this table would be increased proportionally versus the stock values.

At cruise the car spends most of its time well into this table so I would think that it should have some impact on the fuel economy or stability of the AFR.

are there any examples for this table with 60# injectors (@58psi) or is this just not a significant for the tune?

thanks

This table has NOTHING to do with static flow rate ("injector size"), but rather how it responds in the nonlinear flow zone in between initial opening and static flow. Going to higher flow rate injectors may either increase or decrease this table, depending on the flow characteristics of the new design. It also has nothing to do with latency or opening delay, which is addressed in a separate table.

Perhaps this article I wrote a while ago may help. Paul Yaw also has a good writeup HERE.

I guest it would be too much to expect that this table would be provided by the manufacturer.

these are great articles which provide absolutely no useful means of determining the proper values for the {B4005} table.

If you use the OEM injectors from a particular vehicle, then you can borrow all the injector tables from that vehicle's calibration... this is the only way to have a B4005 that matches your injectors.

Quote:

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Originally Posted by joecar

If you use the OEM injectors from a particular vehicle, then you can borrow all the injector tables from that vehicle's calibration... this is the only way to have a B4005 that matches your injectors.

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Very good, I believe the siemen 60# short injectors are used in the LS7, so would that controller have the corresponding table for Gen III motors?

This is the B4005 table from the 2007 C6 Z06 7.0 Litre. It actually looks like how I would expect a larger injector to react. Is this what I'm looking for?

LABELS Small Pulse Adjust (Milliseconds)
mS Value
0.000 0.000000
0.125 0.312500
0.250 0.242188
0.375 0.156250
0.500 0.070313
0.625 0.015625
0.750 -0.007813
0.875 -0.031250
1.000 -0.046875
1.125 -0.054688
1.250 -0.046875
1.375 -0.054688
1.500 -0.054688
1.625 -0.046875
1.750 -0.046875
1.875 -0.046875
2.000 -0.046875
2.125 -0.039063
2.250 -0.039063
2.375 -0.039063
2.500 -0.039063
2.625 -0.031250
2.750 -0.023438
2.875 -0.031250
3.000 -0.031250
3.125 -0.023438
3.250 -0.015625
3.375 -0.023438
3.500 -0.023438
3.625 -0.023438
3.750 -0.023438
3.875 -0.015625
4.000 -0.015625

I would say yes go ahead and give it a try...

copy/paste all the tables that you can... you may have to "hand fit" some of them.

(be sure to save as a new filename)

I haven't done this [yet], so hopefully someone who has will chime in.

This is what I used for my LS7.
"It's all hand fit."

Quote:

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Originally Posted by acric5

these are great articles which provide absolutely no useful means of determining the proper values for the {B4005} table.

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That's because it takes a fair amount of R&D with a a variable injector driver and flow bench to generate the data in the first place. It's not something that one derives after the injectors are installed in the vehicle. I've been encouraging all the injector suppliers/manufacturers to "get with the program" and spend the time/money to generate the necessary data to use their products correctly.

Quote:

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Originally Posted by acric5

Very good, I believe the siemen 60# short injectors are used in the LS7, so would that controller have the corresponding table for Gen III motors?

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Nope. LS7 uses a very different injector that's ~43#/hr.

Quote:

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Originally Posted by eficalibrator

Nope. LS7 uses a very different injector that's ~43#/hr.

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Well then would the ZR1 injectors at 48#/hr be more correct?

LABELS Small Pulse Adjust (Milliseconds)
mS Value
0.000 0.000000
0.125 0.414063
0.250 0.359375
0.375 0.281250
0.500 0.218750
0.625 0.164063
0.750 0.125000
0.875 0.078125
1.000 0.039063
1.125 0.023438
1.250 0.015625
1.375 0.007813
1.500 0.007813
1.625 0.000000
1.750 0.007813
1.875 0.007813
2.000 0.007813
2.125 0.007813
2.250 0.015625
2.375 0.023438
2.500 0.023438
2.625 0.023438
2.750 0.031250
2.875 0.031250
3.000 0.031250
3.125 0.031250
3.250 0.023438
3.375 0.023438
3.500 0.023438
3.625 0.023438
3.750 0.015625
3.875 0.007813
4.000 0.000000