by sike_145 » Tue Oct 15, 2013 9:54 pm
Here is some my thinking about what is going on based on Deman's information that provided to me. I also replay this on PM to you Deman, but I think that this message is not going to reach you because it stays in my outbox (I also have 2 more messages in outbox...what is this mean??)
...
Let say this way...I'm on highway cruising on 2000 rpm with some amount of gas pedal pressed. Now, I just press "pedal to the metal"...100% of gas pedal.
So, in case of my ECU data, I'm looking for driver wish maps...781F4 or 793A4 (which one, why is there 2 maps?). Let say that I look to 793A4 map...so on 2000rpm and 100% gas pedal, IQ should be 70 mm3 (or mg?).
Now, I look to 7827C (if this is fuel temp map), and there I can see only temperatures in range 80 - 90 'C. So let assume that fuel temperature is below 80 'C, so this limit map is not applyed. Correct?
And I still have wish of 70 mm3 of fuel...
Next, go to torque limiter at 7872E; there I can see for 2000 rpm IQ limit is 60,1 mm3 of fuel. Now...I'm on 60,1...
And next is smoke limiter map at 78A20; there is limit of fuel quantity based on rpm and airflow, so now I look at line where 2000 rpm is and need to know how much air I have in engine. Let's say that there is about 700 mg (or mm3?) of air supplyed to cylinders at the moment...and IQ limit there is 47 mm3 of fuel, so I actually have only 47mm3 of fuel supplyed to cylinder?
This is actually air/fuel ratio of 14,9 : 1.
Is this correct?
But...where is in this calculation boost pressure, fuel pressure? Something is missing so I think that there is something more to calculate.
And also...let say that second or two after I pressed gas pedal to 100% air flow increases over 1000 mm3, bur rpm stays on 2000, or just little above (let say 2250).
All previous calculation is still valid, except:
- torque limiter map now shows 60,2 instead 60,1
- smoke limiter shows 70 instead 47
1000/70 is about 14,3, so air/fuel ratio is little richer and goes to more power and torque. BUT...torque limiter says 60,2...so actually there is no 70 mm3 of fuel but 60,2 mm3, and that is 1000/60 = 16,6...which is lean.
So, is al that I said correct or there is some other things to calculate?
I assume, that if IQ is to be increased, it should also be increased turbo pressure (more air) and fuel pressure, so SOI and injection duration maps should not to be modified. But, if more fuel have to be burned...there is more time needed for this...so does this correction is done by original SOI and duration maps or they also should be modified?
And forgot to ask...where are SOI and duration maps in my ECU file?