Is Injector Pulse Width / Duty Cycle accurate?

[dan_t]

Has anyone had issues with the Injection Pulse With Bank 1 / Bank 2 PIDS? Or the Injection Duty Cycle PID?

I've been scanning an 09 Charger (supercharged). HPTuners says we're at 84% DC on 60lb Injectors at mid 4XX whp with 11:1 AFR

Fuel pressure has been checked and is maintaining 58-60 psi until red line.

If I get a chance I'll scope the Injectors tomorrow and see if the PW is the same.

[Homer]

Are you using calibrated fuel mass vs injector pulse maps from the injector supplier or are they modified?

[dan_t]

They are as supplied I believe. Would that have an effect on the listed PW though?

The ECU is making its PW calculation from that table, but if we modify that table we may get more/less PW but ALSO get more/less fuel no?

[Homer]

Well if you are not sure of the tables, how sure are you that the injectors are indeed 60lb? For example, I have seen magnuson/ledelbrock SC vendors supply varying injector sizes over the years from 48lb, 52lb, 60lb and I recently seen some vendors supply HC 62lb injectors with kits. Usually the 6lb kits had the smaller injectors whereas the 8lb kits have been coming with ~60lb.

[dan_t]

I see where you going with this, I should have access to the vehicle today. Its a vehicle that we tuned around a year ago so the INJ/PW table isn't fresh in my memory but the owner was confident they are 60# and the VE table looks realistic.

I'll see if I can pull the # from the Injector itself.

Was I thinking along the right lines of the Inj PW in the PID isn't a calculation, but an actual delivered PW?

Inj # 0 280 158 298
https://www.bosch-motorsport-shop.co...-ev14-injector

[Homer]

My understanding is the fuel mass is calculated and the PW is derived from the tables.

[dan_t]

Ok thats great information thanks. So the INPW could just be showing me something other than actual delivered PW.

Time for me to find the data on these injectors and confirm those tables.

Interestingly InjectorDynamics calculator says that with these injectors and 9psi fueling may be marginal.

[dan_t]

Injector Data was copied from - https://forum.hptuners.com/showthrea...l=1#post404885

Bosch 60lb gt500 injectors 0280158298:
InjPW vs Fuel mass:
0 0
0.00021875 0.032
0.001203125 0.128
0.0034375 0.232
0.004 0.328
0.0045625 0.432
0.00540625 0.528
0.0061875 0.632
0.006921875 0.728
0.008078125 0.928
0.01203125 1.232
0.01553125 1.728
0.090125 10
0.695046875 100


Fuel mass vs InjPW
0 0
0.032 0.00021875
0.128 0.001203125
0.232 0.0034375
0.328 0.004
0.432 0.0045625
0.528 0.00540625
0.632 0.0061875
0.728 0.006921875
0.928 0.008078125
1.232 0.01203125
1.728 0.01553125
10 0.090125
100 0.695046875

[coanan]

I'm now running DW 65# inj with Walbro 400lph. Today at 9.5# boost i was at 41.1% duty cycle.
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[06300CSRT8]

Duty cycle isn't effected by your settings. Your injector settings will determine the pulsewidth the ECU commands. The duty cycle is just math of the pulsewidth versus engine rpm and total time the injector COULD have been open before it is considered static. Its just basic math. If you had the wrong injector settings it would result in you getting too much or too little fuel, but wouldn't make the duty cycle inaccurate. Duty cycle would go up, accurately, as you are commanding more fuel.

[benjohns]

im looking at the same injectors for my hemi does anyone have the correct data