Power FC Different AFRs depending on conditions
06-14-17, 09:30 AM
#1
Different AFRs depending on conditions
When logging AFRs to make adjustments to your fuel tables, obviously there are different things you can do with your car to obtain the data points.
It's easy to do cruise and full boost because there is only 1 reasonable way to record data for those cells.
However, when it comes to areas like the 0 psi row or the 3 psi row, are these better to record while transitioning from cruise to boost (the way you would on a full boost log)?
Or just by maintaining constant throttle to maintain the pressure (similar to the way you would do a cruise log)?
Thus far I have done it the first way, but it results in a big fuel dump in the corresponding cells to achieve the desired AFR. Then if I hit those cells while not in transition (like when going up a hill on the highway) I'm running super rich and the car bogs
These are my fuel curves showing the extra fuel getting added in the first "hump"
It's easy to do cruise and full boost because there is only 1 reasonable way to record data for those cells.
However, when it comes to areas like the 0 psi row or the 3 psi row, are these better to record while transitioning from cruise to boost (the way you would on a full boost log)?
Or just by maintaining constant throttle to maintain the pressure (similar to the way you would do a cruise log)?
Thus far I have done it the first way, but it results in a big fuel dump in the corresponding cells to achieve the desired AFR. Then if I hit those cells while not in transition (like when going up a hill on the highway) I'm running super rich and the car bogs
These are my fuel curves showing the extra fuel getting added in the first "hump"
06-19-17, 12:09 PM
#5
That seems like good advice
I would need to then look at "Accelerate Injector (ms)" and "Inj vs. Accel TPS1" sections
I believe I'm running stock settings for both of those.
Looks like it would be effective to adjust the "Accelerate Injector (ms)" table first, based on the affected RPM range
I would need to then look at "Accelerate Injector (ms)" and "Inj vs. Accel TPS1" sections
I believe I'm running stock settings for both of those.
Looks like it would be effective to adjust the "Accelerate Injector (ms)" table first, based on the affected RPM range
06-21-17, 09:18 PM
#6
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As you said; idle cruise, and full boost are easy.
The other areas which are low boost transition are a problem.
You probably notice that some lower rpm cruise cells are also use for low rpm and lower gear acceleration.
That is a problem because the PFC does not have a 3D or TPS level fuel map.
Thus I add extra fuel just above the cruise areas. I normally do a series of low rpm and lower gear medium acceleration AFR logging runs. I try to adjust for 12 AFR at vacuum or low boost. Then with real driving adjust the fuel for best feel.
Thus the map look weird as compared to Mazda's. But Mazda tended to make the map very rich in some areas instead of optimizing for power. I see your map has some of the same quirks as mine. Low load areas have a sudden leap in fuel to account for acceleration.
My attached fuel map is for a FP HTA GT3582R with a 3 bar map sensor. I also use a manual idle control with a homemade AC only idle solenoid. The weird P19 row is about 18.5 psi with an AEM 50/50 water meth kit with a constant flow rate. My setup also has a strange harmonic flow around 4800 -5200 rpm. Almost stock N columns except my N1 = 800, N19 = 8000, and N20 = 9000.
The other areas which are low boost transition are a problem.
You probably notice that some lower rpm cruise cells are also use for low rpm and lower gear acceleration.
That is a problem because the PFC does not have a 3D or TPS level fuel map.
Thus I add extra fuel just above the cruise areas. I normally do a series of low rpm and lower gear medium acceleration AFR logging runs. I try to adjust for 12 AFR at vacuum or low boost. Then with real driving adjust the fuel for best feel.
Thus the map look weird as compared to Mazda's. But Mazda tended to make the map very rich in some areas instead of optimizing for power. I see your map has some of the same quirks as mine. Low load areas have a sudden leap in fuel to account for acceleration.
My attached fuel map is for a FP HTA GT3582R with a 3 bar map sensor. I also use a manual idle control with a homemade AC only idle solenoid. The weird P19 row is about 18.5 psi with an AEM 50/50 water meth kit with a constant flow rate. My setup also has a strange harmonic flow around 4800 -5200 rpm. Almost stock N columns except my N1 = 800, N19 = 8000, and N20 = 9000.
Last edited by cewrx7r1; 06-21-17 at 09:25 PM.