I have the same doubt of gionag why to a value iq are related a lot of pressure in the rail...? I think the solution is to see at 3000 rpm, what is it ? the real pressure that runs the rail and in this way you can? find the value to change
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I have the same doubt of gionag why to a value iq are related a lot of pressure in the rail...? I think the solution is to see at 3000 rpm, what is it ? the real pressure that runs the rail and in this way you can? find the value to change
as always, I return to the accounts...by the accounts from the map stock, in many cases, the injection ends much before TDC to 10 degrees before.....maybe something wrong :(
I don't know if all correctly interpreted the maps.
the information dependent on the rpm is only on the map of rail pressure
the map duration injection is not dependent on the engine rpm.
the maps SOI instead depend on the rpm
the flow rate of an injector is not ? proportional to the variation of pressure, much less exponential.(mathematically paralando but if you want feel free to smentirmi)
the flow rate(true iq) increases with the square root of the pressure increase...
then the dual of the rail pressure is not equivalent to double the flow injector but "only" to 1/4...
the formula ?:flow2=flow1*sqrt of press1/press2....
all right, but the me problem ? always the one , maybe I can understand my doubt....you can make a practical example with real data taken from the map so maybe I can understand ..thanks
what? specifically, your doubt??
then, since I can't explain it well I will give you a practical example of the problems where do I...first thing's first, I take the map and SOI fixed a certain number of turns, in this case, 4500, and I'm going to see the values of the last 3 IQ that match : 75, 70 and 65 mm3 https://www.dropbox*****/s/z9lbclebvt...9.29.png now... I see that these IQ(have the same value), the injection begins at 896*0.976(conversion factor) = 874,4 us , this value to 4500 RPM is equivalent to(874,4*6*4500) /1000000 = 23,6 ?...
well now I move to the map of the duration, and I see that the last 3 IQ of bp are : 70,3 70,2 70 ...of course I can't find the rounds because this map ? as a function of rail pressure ...now I think (smentitemi if not ? cos?) that at 4500 RPM my rail pressure ? to 1350 bar(but I can't know with certainty why? the pressure also depends on the percentage of the pedal that I require of you) and here I go on with the calculation by finding the degrees of duration for the last 3 IQ corresponding to 1350 bar https://www.dropbox*****/s/op9e8g8eis...2014.30.28.png the map tells me that my injection lasts 871*0.976 = 850 us ,that at 4500 RPM (it is assumed) is equivalent to(850*6*4500)/1000000 = 22.9? , this calculation leads me to think that the injection starts to 23.6? before TDC and ends 22.9? after....but the fundamental problem ? that from a log that I did not always 4500 rpm correspond to 1350 bar, also when the thrust of the foot, the pressure reaches 1350 bar at 3200 rpm , but if I accelerate a little to 3200 rpm the pressure ? 1000 bar....then how do I calculate if I don't know what values to enter in the formulas ? for example, how do I know ,in the map SOI , 3000 rpm, at which the curve is in the map duration ? help me to clarify please
guys when I wrote this sentence "this calculation leads me to think that the injection starts to 23.6? before TDC and ends 22.9? after" I was wrong why? you can? understand 22.9? degrees after TDC , instead I meant to 22.9? after the start of injection ...sorry
first thing in the advances are converted directly with the factor 0,023437....then where to 4500 rpm read 896 you're 21? of advance...now you know that to inject those iq that you were talking about before at those rpm the ecu always uses 21? of advance...
moving in the injection times for those iq have durations of injection 22.9? as you calculated....
now your beginning to 70mm3 starts at 21? the first of the pms lasts from this point onwards for 22,9? then ends up with 1.9? after the pms...
the speech that you linked to press rail>iq and rpm and gi? all calculated from the ecu to the different conditions of use....
now you only affects the area of the map where you want to inject all the fuel that you want to assume that you have both at a high rpm and "loads"...the other areas of the "intermediate" why do you want to change?? do you want to complicate your life?
and anyway, if you really look, maybe with winols the map times you'll see that for e.g 50mm3 of diesel 300 bar, you will have a time of 3-4000 us to 1350 that time is reduced with the formula that I posted recently for the calculation of the press...
so...
ah..I forgot...don't focus only on the rpm...logs into the injection times and press the rail in conjunction with the iq...you will see that you will understand the connection...