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I had a question about the IFR data when using a ADM Fpcm. Car is 2 bar SD. When using variable pump pressure, say 50psi low, 60psi normal, and 65psi high. Do I flatline the IFR injector data, maybe 58psi or more, like a car with a boost dependent fuel pressure regulator? Or is it better to leave the IFR data the way it is listed in the Fuel Injector Connection data pdf, even though the rail pressure will be changing?
Don't flatline anything. Use the data they provided. Perhaps I'm wrong...but I don't know why you would ever flatline any IFR data if you have the ability to monitor FP and MAP properly (which the 2 bar does). The fuel pressure is changing, and the MAP is certainly constantly changing. Being able to read both allows for a greater precision of fuel delivery.
Do you have a 3 bar MAP sensor in your car? And the right settings in your tune to read the 3 bar properly?
It has a 2 bar map sensor and it is logging properly. But if I use the desired fuel pressure data from ADM, it progressively ramps the fuel pressure up. So I was under the impression that it would almost simulate a rising rate fpr. So setting the Ifr table to a static setting like when you do actually have a boost dependent fpr. In the FIC data table it states if you are using a rising rate fpr, to flatline the IFR table at the 58psi, or 400kpa flow rate, which turns out to be in the 72lb/hr neighborhood for this injector, the FIC 60lb/hr or 613cc. So I should just leave the FIC predefined data in the IFR table even though the fuel pressure is rising too?
I've got the ADM FPCM as well (on my ZL1 pump) so I know it well. The FPCM is not boost referenced like a traditional return style system with a referenced reg. It is not progressive. It switches to different commanded pressures depending on flow. So you can't assume that the pressure differential (FP - MAP) will remain a constant when in boost like you might do with a traditional boost referenced return/reg system. It will be variable...and the FP switches rather abruptly. Furthermore, the fuel pressure can drift down even in high flow mode if you're using enough fuel.
Hope I'm making sense. Bottom line....the pressure differential will be moving all over the place, and at times changing rather abruptly. The injector data should not be flatlined. They need to be constantly adjusting to the constantly changing pressure diff.
Here's a decent read on the ADM FPCM with some data logs where you can see how abruptly the FP can jump when switching between the different flow modes. http://www.camaro5.com/forums/showthread.php?t=268524
Ok, so I will just use the injector data from FIC, fpcm data from ADM, and I should be fine then? Thank you for walking me through this. I really appreciate it. So as the FP changes my Ve table will probably have some not so smooth transitions in it to keep my desired a/f then I would assume.
No problem. Happy to help. And "Yes" to all things you mentioned above. Use the FIC data. Use the ADM data. VE may indeed have a few interesting spots where the FP transitions. I plan to log and analyze some of this myself (but haven't yet...waiting for the salt to get off the roads here). So I'm really not sure if this will happen or not. But like you, I kind of expect to see something. Just log your FP, AFR, and commanded in the chart and look at the transitions. I suppose it depends on how fast the ECU is in adjusting the injectors vs FP. My guess is it's pretty fast. But also keep in mind that the FP sensor is way back at the tank. So pressure at the rail may not be exact timing as what the ECU reads. Again...I really don't know this yet but plan to take a look. Maybe someone else here who's already messed with this will chime in.Quote:
Originally Posted by h2.4
Depending on how much fuel I need vs the output of the pump....I may take the ADM settings and lower them all down. Maybe run everything at 58 psi. You could also set everything to 58 psi for just the VE tuning and switch it back to the ADM settings after your VE and MAF are tuned in just to try and eliminate the pressure spike effects (if any). I think the ADM settings are designed to provide maximum output. Depending on your set up...you may not need that.
Thank you. I will be getting this set up hopefully in the next couple days, we'll see how it goes.
hey i think i am experiencing what you were talking about with the adm fpcm and fuel pressure drifting down in high flow mode but it isnt running lean adm claims the pump should be supporting my power level at 10# boost. but it seems to me that the pump just cant compensate rapidly enough. is this thing working correctly or do you think the data or something is wrong? i used the zl1 data and i read the zl1 data did not work for everyone. which data did you use? adm hasnt been much help told me i needed bigger injectors so i got 90s and fuel pressure drops even more