E39 Project
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Stock DME Tuning wont work.....well it can, but not without a piggy back of some sort. The DME has no input for boost pressure. With a Supercharger you can use AlphaN tuning because everything is linear and mathematically sound. Turbos are not.
It simplys measures flow? MAF no? Many people tune this stock ecu so I know I'm not too wrong.
We will be using a datalogger of some sort, and log the stock maf voltage, and also the ford MAF we will be using, and then I will swap out the stock one, and be able to monitor the increased amount of airflow.
sk8 or die
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Yes, it measures mass airflow. This is great as long as the pressure doesn't change. Due to the constant weight of the earths atmosphere, the computer knows the pressure will never vary from 14.5 PSI. So it measures Airflow, based on that pressure. If the pressure increases, due to a turbo or supercharger, the Airflow can remain the same but the DME doesn't know that an increased air amount has entered the engine.
ALL DME tuned supercharger kits on BMW's that used to be NA convert to alphaN. This eliminates the MAF's and uses math to figure out airflow based on RPM. Because a supercharger produces the same PSI at a particular RPM all the time, the equations can be figured out and this programmed in.
Turbo's are a different beast. They produce boost based on load. If you are cruising at 4K RPM the turbos will produce 0 PSI but if you are accelerating, when the car hits 4K, the turbos could be producing any amount of PSI, based on many factors. This is why Mas Air Pressure (MAP) must be measured in a turbo car. Since these cars have no factory MAP sensor, one must be added and controlled, and have bearing on the fuel tables.
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Yes, it measures mass airflow. This is great as long as the pressure doesn't change. Due to the constant weight of the earths atmosphere, the computer knows the pressure will never vary from 14.5 PSI. So it measures Airflow, based on that pressure. If the pressure increases, due to a turbo or supercharger, the Airflow can remain the same but the DME doesn't know that an increased air amount has entered the engine.
ALL DME tuned supercharger kits on BMW's that used to be NA convert to alphaN. This eliminates the MAF's and uses math to figure out airflow based on RPM. Because a supercharger produces the same PSI at a particular RPM all the time, the equations can be figured out and this programmed in.
Turbo's are a different beast. They produce boost based on load. If you are cruising at 4K RPM the turbos will produce 0 PSI but if you are accelerating, when the car hits 4K, the turbos could be producing any amount of PSI, based on many factors. This is why Mas Air Pressure (MAP) must be measured in a turbo car. Since these cars have no factory MAP sensor, one must be added and controlled, and have bearing on the fuel tables.
So what you are saying here, is the countless stock DME tuned turbo e36's and e46's are unsafe even though people have driven tens of thousands of miles and also daily drive those cars? I honestly can't believe that it doesn't work when so many people prove it.
Hell they made over 1000whp on the stock e36 DME.
I know there are other factory turbo cars with MAF based systems as well.
What you said does make some sense to me though.
Pv=nrt
No? Haha.
sk8 or die
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So what you are saying here, is the countless stock DME tuned turbo e36's and e46's are unsafe even though people have driven tens of thousands of miles and also daily drive those cars? I honestly can't believe that it doesn't work when so many people prove it. Hell they made over 1000whp on the stock e36 DME. I know there are other factory turbo cars with MAF based systems as well. What you said does make some sense to me though. Pv=nrt No? Haha.
This is how I understand the DME, the ones I've seen have all had some sort of piggyback controller, or an archaic RRFPR. I never claim to know everything, just explaining how I understand things. I'm always eager to admit I'm wrong when I get to learn something new.
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