MoTeC Global Forum

Hey guys,

I've recently upgraded my injectors from Bosch 363's to a set of Siemens 910cc (p/n FI11405) 2.35ohm low imp.
Engine is an RB30et - group fire using M4 ecu - old injector current setting for the 363's was '12' (6 doubled for group fire) info taken from the list of values for common injectors in the help of the emp software.
Injector scaling set at '5'.

Excuse my lack of knowledge but, how do I know what figure to use for injector current for these Siemens injectors.
General Setup -> Main Setup -> Injector Current IJPU = ?
and also
Do i need to change the value for injector scaling
General Setup -> Main Setup -> Injector Scaling IJCU = ?

Any help with figures or general info would be greatly appreciated

Regards

Ollie

We have tested these injectors here. The current setting needs to be 3 (6 for group fire) and peak hold ratio 4. FOr the Injector Battery COmp you will need to select "-1" and put in a user defined table based on the following values, choose the values apropriate to the fuel pressure you are running:

Code: Select all

Fuel Pressure (bar)            
Volts                           3              4              5              6
10                             933          982         1003           918
11                             839          856           880           803
12                             797          746           784           713
13                             653          679           715           640
14                             626          643           646           590
15                             579          588           597           567

Firstly, thanks for the prompt reply and detailed information, that kind of info is hard to obtain at the best of times, so much appreciated.

When u say peak and hold ratio - 4 ?
do u mean injector scaling ? should that figure be 4 ?

Regards

Ollie

Ignore the peak and hold ratio, it is an M800 Parameter! Sorry.
You don't necessarily need to change your injector scaling. You can apply an overall trim to the fuel table to get the fuelling roughly correct with the new injectors. For example if you have a flow increase of 30% in flow rate you would apply an overall trim of 23%. You can then use the Tools Menu (F9) to apply this trim to the table.