[drfrink24]

I found this searching:

(IPW + IDT)/ ((120/rpm ) x 1000) = IDC IPW = Injector Pulse width ms IDT = Injector dead time ms IDC = Injector duty cycle

Using IDT of 1.35ms

Doing some baseline logging on StreetTuner last night, and running the calculations, I'm seeing as high as 102%. This is of course, with the v1.04 basemap with NO tuning (yet ) ..

Am I doing something wrong in my calculations?

Car:
2004 STI
Snorkel Removed/Panel filter
Helix catted DP + Borla Hush
Boral coated headers
Walbro 255lph pump

[WolfPlayer]

I do my IDC calculations using the formula of IPW * RPM / 1200. I have ignored the IDT. In any case, after some boost and ignition tuning I was getting about 102% IDCs .... I guess that would be more if I included the IDT. After leaning her out a big the IDCs came down to the mid to low 90's ... and I still have more leaning out to do. However, I want to rescale the load in my tables before I lean it out anymore than I have.

I don't think you need to use IDT (IMHO). If the injectors are always open (i.e. static) then the dead time is moot and they are just open 100%. The IDT doesn't matter when the injectors are static.

t

[jays05]

Using the IPW * RPM / 1200 formula I have seen IDC's as high as 103 during 20psi+ boost spikes when I was tuning for the perrin EBCS. The car got plenty of fuel and did not lean out. I seem to remember reading somewhere that STI injectors can be pushed to around 110-113% before they are "static" or wide open.

[WolfPlayer]

Originally Posted by jaygoesfast

I seem to remember reading somewhere that STI injectors can be pushed to around 110-113% before they are "static" or wide open.

Scott Segal said that. Of course, I don't understand how that is even possible ... unless the reported values in the datastream don't jive with reality.

t