adjusting injector pulse width 160LB injectors

[KevsfastZ]

Hey guys,


I'm having an issue with getting my idle dialed in.

Car is a 02 Z28 with an 8.5:1 347 single front mount speed density.

As of now, I have my base fuel pressure at 35lbs, my injector duty cycle is at 1% at idle with the AFRs at 11.5ish, and I am unable to lean it out anymore. Can I adjust my injector pulse width in order lean the motor out more at idle? All i have changed is flow rate VS KPA.

Thanks in advance!

Kev D

[DSteck]

You can use short pulse adder and the offset tables to bring it down, but first you need to I to the transient tab under fueling and change the minimum fuel mass to 0.001. That value is a floor for injector pulse width.

[KevsfastZ]

You can use short pulse adder and the offset tables to bring it down, but first you need to I to the transient tab under fueling and change the minimum fuel mass to 0.001. That value is a floor for injector pulse width.

At what values should I adjust these at? Should I creep down in 10% increments? ( injectors.jpg attachment)

Where exactly do i need to change the minimum fuel mass? (transient fuel.jpg attachment)

Sorry for not understanding fully.

[Alvin]

Thats honestly going to be pretty tough to do. Why such big injectors? We use the same on a 1000 rwhp car on E85 and they still have room to go. On gas they would make a ton of power.

[DSteck]

At what values should I adjust these at? Should I creep down in 10% increments? ( injectors.jpg attachment)

Where exactly do i need to change the minimum fuel mass? (transient fuel.jpg attachment)

Sorry for not understanding fully.

Min Fuel Milligrams -> make it 0.001.

You can lower the short pulse adder however you want. There's no real systematic approach unless you wanted to back-calculate a bunch of crap based on injector flow rate, current pulsewidth, and your wideband value.

[ccrp]

do you run high or low impedance injectors like via an AEM box?

in that case you can go down in min. inj. pulse to something like 0.5msec. My 160lbs injectors idled nicely at 14.5 AFR

[KevsfastZ]

do you run high or low impedance injectors like via an AEM box?

in that case you can go down in min. inj. pulse to something like 0.5msec. My 160lbs injectors idled nicely at 14.5 AFR

They are high impedance, could you post up your tune so I can use it for reference?

[KevsfastZ]

Min Fuel Milligrams -> make it 0.001.

You can lower the short pulse adder however you want. There's no real systematic approach unless you wanted to back-calculate a bunch of crap based on injector flow rate, current pulsewidth, and your wideband value.

should I lower everything across the board? say multiply the whole table by 0.95 and go from there?

[ccrp]

here you go

not the absolut final one but ran well enough to hit 215 mph in the standing mile.Howveer disregard the spark tables on this one

[KevsfastZ]

After changing Min Fuel Milligrams to 0.001, and adjusting the short pulse adder, I was unable to get my pulse width lower then 1.8 which it was prior to adjusting.

I feel like I am missing a table, can you guys point me in the right direction.

Thanks in advance,

Kev D

[DSteck]

Post the file.

[KevsfastZ]

Here is the tune, all that is changed at the moment is Min fuel Milligrams

[505outlawz]

Did you ever get this figured out?

[tt383lt1]

do you run high or low impedance injectors like via an AEM box?

in that case you can go down in min. inj. pulse to something like 0.5msec. My 160lbs injectors idled nicely at 14.5 AFR

i just got these same injectors. can you tell me how you got a good idle with the 160lb, i was told there hard to get to idle good.