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Old 07-15-2011, 07:16 PM   #9 (permalink)
dcb
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pimp mobile - '81 suzuki gs 250 t
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I assume you are doing this in public to build some peer consensus. I am not sure you know precisely what you are measuring if looking at the output from the ECU, and it is critical to understand that if you are trying to measure transaxle efficiency. I have seen a lot of ECUs report bogus or computed data, so there isn't a lot of point in the data analysis without first figuring out what you are looking at, hence why I am asking for particulars about the system in question. I appreciate it is a bother to double check what the ECU says but there is good reason for it.

For example you did not mention current sensors on mg1, so is the ECU inferring the current there? and if so, it is not possible to use that reading to determine the efficiency of anything relating to mg1.

Also since it appears to use current to derive torque, we don't know if it is "electrical" torque, or shaft torque after converting for losses, or how accurate the current to torque conversion reading is. Could be a 30% discrepancy there depending how the ECU programmer interpreted the "requirements" if any.

Also, did you mention publishing data? Assuming the data is correct (or even if it isnt), it would be simpler to process things like "positive area under the blue line vs negative" with the actual values.

But I do need to understand how things like what the ECU reports as torque relate to the real world before I will accept ECU funged data. Just like I wouldn't accept airflow as an approximation for fuel flow where precision is concerned. I have no other purpose here accept to ensure the claims are valid, and taking measuring shortcuts is rightfully going to draw some criticisms. I'm glad you are willing to do it, but I will pressure you to do it "right" before "publishing" any conclusions.
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Last edited by dcb; 07-15-2011 at 07:33 PM..
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