EV14 injector closing time

[A80Avant]

what ill do is try marcel's advice on my config B so i can see the differences.
then ill report back!

[prj]

I saw that video before, sorry, too much to translate...
The values I gave are offset or dead time, which is closing time minus opening time (or vice versa? too tired to think).

This is basically the time that the injector "does nothing", and this is the one the ECU needs.
I think it's the same value regardless whether you are running VEMS or Motronic.

In Motronic it calculates the amount of time the injector should be open to reach the target lambda defined by tables based on MAF value and injector size, then adds the "dead time" to it, to get how long the actual injector pulse should be to reach that opening time.
Motronic does not have a VE table to code this into, so it is very very important to get this right, or actual will never match requested from table at low pulsewidths.

Also, if you get this right on VEMS, I think you should not need to alter the VE table when changing the injectors.

[A80Avant]

Yes indeed.

Vems had a more generic setting previously and now have added the voltage compensation, so after changing all these I still had to redo the fueling table.

However I'd like to have these basic stuff correct from the beginning so that they are in and work fine

sent using Android

[A80Avant]

Injector dynamics also suggests using the values given from the manufacturer, as measured with an oscilloscope and to be able to derive the closing time alone is near to impossible.

If I do try the vems guys theory ill par back.

sent using Android

[A80Avant]

Right,
tried briefly the 0.3x given ms on every voltage.

The result was that the fueling table had to be increased little less than double (from 81 to 131) on idle and similarly the rest of the table will be higher than that anyway.

once the car was on idle and fan was kicking in, i was switching between configs, and honestly, i couldnt see much difference. Of course ill run more tests and try to make the table more accurate to see if overall you get a better feel, but i doubt it would be noticable.

Ill report back with more info once i have time to spend on cruise mapping.

Also tried the autotune feature, its ok, still like the manual way better

[Jamo]

Interesting, I had the reverse my idle VE went to 85 from 88 with pulsewidth being about 0.7 - 0.8 ms IIRC

[A80Avant]

It may be the difference of a lot of things between engines, it mine still is slightly higher than 1ms on idle. I didn't check on the new settings

sent using Android

[prj]

Well there is no way any EV14 has 0.3ms dead time at 14V. It is more than double that.
At least 0.7ms on smaller injectors and 0.9ms+ on larger ones.

[A80Avant]

we know that,
i am only trying out a suggestion by the developers on what values would produce an easier fueling map to work with. I think they shouldnt even call it dead time table according to their description, but obviously in order to get the results you want you are always second guessing, whereas, from factory you have a proper set of values to play with.

[A80Avant]

small update,
i held my ground and used the supplied values from the company on the EV14, and have no issues whatsoever. Actually its nice that on boost, the fueling table becomes more elaborate and i can have multiple values until i reach my target lamda, whereas previously i could easily jump from one value to the next in a big leap, making tuning slightly more difficult.

Also, the developers dropped the validation error that was popping up on the latest vemstune software, so basically they realised there isnt anything wrong with using high values in the voltage compensation.

[Jamo]

So what values did you use? they've updated the help file and made it very confusing reading so they want users to subtract the close time value but that value isn't stated anywhere.

Would have been better if they could have stuck to the global standardisation spec used for injectors.

[A80Avant]

Yes, that is what I was told as well, but the closing time is not measured or known to most of us, so instead I used the values sent by FIC to me, specific for my injectors. I can see that comparing to cruising, idle values are much smaller, but the car comes well, so I don't mind

sent using Android

[A80Avant]

values i used were:

2.55/1.70/1.20/0.92/0.75 in ms for 8/10/12/14/16 respectively. These were measured at 60psi or 4.1bar and as my fpr is 4bar, they were the closest ones for my setup.

[blackS2]

Does somebody has latency values for the BOSCH 0280158040 EV14 - 980 cc/min Injectors?

Is somebody using them in S2 engine?

regards