Injectors - dead time - voltage - pressure

[superkarl]

just trying to interpret this data:
https://docs.google.com/file/d/0B-z7ncRSik0peld5clJIZ0pTZ3c/edit?usp=sharing
supplied by USRT.
i like to understand things you see.

now from what i know injectors have a 12v feed. so why the data for other voltages?
the differences in dead times seems quite big between say 12v and 14v.
but they dont alter a great deal with differences in fuel pressure (3bar - 7bar)
if you run at standard 3bar, with 12v feed, the dead time will be 1.12ms. rising to 1.17 if running say 2bar boost.

just trying to understand this a whole lot more basically, i like to be a nerd. If someone has good knowledge of this sort of thing please share.

 

[beachbuggy]

just trying to interpret this data:
https://docs.google.com/file/d/0B-z7ncRSik0peld5clJIZ0pTZ3c/edit?usp=sharing
supplied by USRT.
i like to understand things you see.

now from what i know injectors have a 12v feed. so why the data for other voltages?
the differences in dead times seems quite big between say 12v and 14v.
but they dont alter a great deal with differences in fuel pressure (3bar - 7bar)
if you run at standard 3bar, with 12v feed, the dead time will be 1.12ms. rising to 1.17 if running say 2bar boost.

just trying to understand this a whole lot more basically, i like to be a nerd. If someone has good knowledge of this sort of thing please share.

The graph is used when tuning TVUB map which is the voltage compensation map. Injectors don't get a pure 12 volts all the time and this map is used to compensate for that.

 

[superkarl]

do they use it to try and keep the dead time the same all the time?

 

[<tuffty/>]

RKTI 11.40 (Calculation of Injection Time ti from Relative Fuel Mass rk) - Nefmoto

<tuffty/>

 

[badger5]

13.8v is more normal running voltage... cranking will be less of course..