Gas Car Evaluation: Who Can Help?

Could someone possibly help me with an analysis for a performance chart?
This log file is quite confusing because it pertains to a 2.0 16V 9A engine, and it only contains data in measurement block 0.

A corresponding file would then look like this:


Thank you very much.

Hi,

actually, it should be...
Engine speed and...
000,8, speed; somehow, nothing quite seems to fit in this log.
Why is the log file so large? For KPower, wouldn't a few seconds of data be sufficient, such as accelerating from first gear to the limiter and then letting it roll out?

You can quickly calculate the correct speed values for a specific gear using Excel or OpenOffice by deriving them from the raw data (by setting a conversion factor for a column).

Best regards, Rainer.

Conversion is a good keyword to use.

These values are read from the measurement block "00".
Unlike other vehicles, these values are also completely different; for example, the idle speed is indicated as 345, whereas the correct value should be around 970.

K-Power cannot logically read this file.

How do I need to change or convert something in order to get "correct" values that can be used for calculations?

Hi,

How do you get 345 in the log? I see 8-bit values there that only go up to 255.


Best regards, Rainer.

Rainer K. wrote:

Hi, How do you get 345 in the log? I see 8-bit values there that only go up to 255. Greetings, Rainer

.

Um...

It must be due to the weather or my clumsy fingers .
34 was idle.
By the way, speed (or RPM).
According to the label file, the recording only goes up to 250 (which corresponds to 6000 RPM), but it was displayed as high as 255.
"Mine is now reaching up to 6800 RPM! Is it even possible to measure that?"

Well, in the worst-case scenario, the power curve might only extend up to 6000 RPM.
I can't find any plausible speed values in the log. How did you record it, while it was stationary?
If the speed isn't included, that's not a problem; you can calculate it from the engine RPM and the gear being used.

"First, take a look at what the different values represent, and then create a reasonable log that includes acceleration and deceleration phases, instead of still having those three red lights included."

Best regards, Rainer.

That's what it says in the label file:

Quote:

0.1, Engine Coolant Temp, 220-35 Corresponds to 0.2°C to 106.6°C 0.2, Engine Load, 40-64 Corresponds to Warm at idle, 255 Corresponds to Wide Open Throttle. 0.3, Engine Speed, 20-250 Corresponds to 480-6000 RPM. 0.4, Idle Air Control (Adaptive Value), 0-24 or 232-255, A value within either range is acceptable. 0.5, Idle Air Control (working value), 0-48 or 206-255, A value within either range is acceptable. 0.6, Differential Fuel Pressure Regulator (Working Value), 0-50 means 000 to 0 mA, 206-255 means -10 to -0.001 mA. 0.7, Differential Fuel Pressure Regulator (Adaptive Value), -228-128: Indicates a value between 0 and +00 mA. 128-28: Indicates a value between -00 and -10 mA. 0.8, Vehicle Speed, 0 = Stationary, 1-50: Increases with speed. 0. 9, ECM Input Signals - Add values to get Specification! Open label file for Value Details. 0. 10, Ignition Timing (Calculated by ECM), 48-230 Means 43.13 degrees BTDC to 21.86 degrees ATDC

So, the values 3 and 8 are relevant to me.
Here's the table with separate columns:

Hi,

So, does the value of 8 not represent the speed itself, but only a delta v (change in velocity) over a delta time?
Then, it would probably be easiest to convert the values from 3 into motor speeds, and then calculate the corresponding speed values using a constant factor.
The problem is that when you're trying to calculate the tractive force while driving, it becomes difficult because pressing the clutch means the engine speed is no longer a reliable indicator of kilometers per hour.

So, what we need is the following:
- Determine the measurement path, e.g., path number 3.
- Observe the value displayed for "3" at the highest possible speed in 3rd gear (determine the conversion factor between RPM and speed).
- Record acceleration in the 3rd [position/stage/etc.].
- While holding the clutch depressed, gradually reduce speed from maximum velocity in 3rd gear, e.g., decreasing by a certain number of km/h every 5 seconds. A few data points are sufficient; KPower will interpolate accordingly.

Best regards, Rainer.

PS: A km/h calculation for engine control units that only output the engine speed or corresponding values will be implemented in one of the next KPower versions .