Injector deadtime value spreadsheet

[dnb]

No readable part number on the Dekas.

[UrSobsessed]

Are the Siemens these?  http://www.siemensdekafuelinjectors.com/60-lb-hr-siemens-deka-fuel-injectors-high-impedance-long-style-ev1-connector/

The "simple" model looks something like this for my small injectors:

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Part number:  0 280 155 931
Assessed size at 3 bar pressure:  259.0cc/min

10v   610.1us
12v   286.5us
14v   52.3us
16v   -129.1us

Note that the negative 16v offset cannot be used.  It is due to the closing time of these injectors being slower than the opening at this supply voltage.  This value should be set to zero.

My larger set of injectors have tested (so far) as follows:

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Siemens DEKA nominal 600cc injectors
Assessed size at 3 bar pressure:  583.3cc/min

8v    864.4us
10v  688.0us
12v  512.1us
14v  307.3us
16v  144us

This is within 20us of the values calculated from the injector data sheet supplied with the injectors.

[dnb]

Not those.  Mine are the shorter, fatter ones.  I think they're supposed to be 57lbs/hr and are a fair number of years old now.

[boostd audi]

Most popular siemens are 60 and 80 here

[lost]

Does anyone have injector settings for Siemens deka 870cc 80lb 110324 injector from vems webshop.

And can 870cc work good for emmision test on idle on 6cylinder 2.0 engine.
My current PW is 1.4ms

https://shop.vems.hu/catalog/siemens-870cc-80lb-injector-p-136.html

[dnb]

My Deka injectors go non-linear below about 2ms pulselength.  At best this will make your VE table look weird at idle and at worst the idle will be very bad and emissions will be suspect since the injectors don't do the same thing from pulse to pulse.

It's easier to tune if you can get the idle to require more than 2ms pulses (eg smaller injectors) but I have found my Deka injectors injected a repeatable amount of fuel even in the non-linear region so you have a good chance of making it work.

[UrSobsessed]

The 60# injectors I posted above run at ~1.4-1.6ms at idle.  I can't say whether they're linear or not but the idle is solid and somewhat reasonable to tune.  There're definitely fluctuations in lambda not seen anywhere else at idle so maybe they're similar in behavior to your 57#ers.

[fphil]

The VDO specs of the DekaVII injectors give the min operating PW at 2% linear error (see the link above). Per example it is 1.2ms for the FI14326 46 lb/hr.

[lost]

Here are deka 4 IV high impedance , looks like minimum PW for them is 1.7... my car idles at 1.4 with them  :'(

[gunni]

Can you put your injector settings for them into the spreadsheet?

[lost]

Can you put your injector settings for them into the spreadsheet?

I will after i test the settings...

[lost]

After changing siemens deka 4 80lb / 870cc injector setting from traditional ( recomended settings from forum)
to simplified setting values from injector PDF i got VE idle from 48 (old settings) to 34. PW is same as before 1.4ms.

Injector deadtime table is injector voltage offset??

[fphil]

"PW is same as before 1.4ms."
It has to be so, no?

"Injector deadtime table is injector voltage offset??"
I believe it is the PW(ms) offset of the regression line of the characteristic injector flow curve, Flow(cc/min) versus PW(ms). for a some Voltage

[gunni]

After changing siemens deka 4 80lb / 870cc injector setting from traditional ( recomended settings from forum)
to simplified setting values from injector PDF i got VE idle from 48 (old settings) to 34. PW is same as before 1.4ms.

Injector deadtime table is injector voltage offset??

Which are the ones that work correctly for your injectors?

1.4ms is the total time so that will always be the same for the same idle airflow no matter your VE values as your deadtime values will have been changed.

[lost]

I removed 870cc siemens injectors and went back to stock injectors, they were too big for 2.0 v6 engine 800rpm idle, it was too low PW on idle, it worked but not 100% smooth on idle.

I suppose they would work gread on 3.0 6-cyl on 2.0 4 cyl engine...