Hi,
im looking for some offsets for conversion from mm3 to mg/stroke.
Thx for reply

mm3 x 0,85=mg

0.835

This figures always stands somewhere in the data. You will need a Damos to find it. 0.835 is pretty close correct. 0.84 is also common

Sorry to ressurect this thread...

The damos file for peugot 807 2,0hdi 16v says that the smoke limiter map is in mm3, and the properties in winols says a factor offset of 0,01 which makes the mm3 numbers look like xx,xx mm3. In this thread, a factor of 0,84 is advised when i want my numbers in mg/s...

If i use 0,84 as offset factor, my numbers look like xxxx,xx

So am i right in assuming that i should be using 0,0084 as offset factor?

Thanks in advance.

There is no simple factor to calculate [mm³/st] into [mg/st.]..

To calculate a volume to a mass, you need its specific gravity and it temperature.
Specific gravitiy is a valit value at 20°C or 293,15K

georgi_a4 wrote:mm3 x 0,85=mg

Hopefully this guy doesnt remap cars nowadays , cuz not the right factor here means u lost some braincells through the years. 0.85 to 8.35 is big comparison that is 2mg/stroke diffecence in 80plus (bigger power calculations) :thumbup: :D

Edit. I mean i hate when "people" are coming here just for counting posts , if im not sure what im talking about i dont speak.

Sometimes time I get the impression that most of the tuners in all that websites are with at least Phd phd in science or at least master degree in physics.. based on post like yours

What`s so wrong for rough estimation by using factor of 0.84? And excuse me if I`m wrong, but arent` there tables in the ECU that take care for correcting the fuel data based on the fuel temperature? I think there are..

Here is a Diesel density at 15 °C = 840 kg/m3 = 840 * 0.001 = 0.84 mg/mm3 based on the popular catalog data..

You think that for 80mm3 and above it will be producing such an enormous issue... Well here is a table with a correction factors (second column) based on temperature (again from the books)

Code: Select all

-40° - 1.0416 * 0.84 = 0.8749 -> * 80mm3 = 70.0 mg = +2.8
-20° - 1.0293 * 0.84 = 0.8646 -> * 80mm3 = 69.2 mg = +2.0
-15° - 1.0251 * 0.84 = 0.8610 -> * 80mm3 = 68.9 mg = +1.7
-10° - 1.0210 * 0.84 = 0.8576 -> * 80mm3 = 68.6 mg = +1.4
-05° - 1.0168 * 0.84 = 0.8541 -> * 80mm3 = 68.3 mg = +1.1
+00° - 1.0126 * 0.84 = 0.8505 -> * 80mm3 = 68.0 mg = +0.8
+05° - 1.0084 * 0.84 = 0.8470 -> * 80mm3 = 67.8 mg = +0.6
+10° - 1.0042 * 0.84 = 0.8435 -> * 80mm3 = 67.5 mg = +0.3
+15° - 1.0000 * 0.84 = 0.8400 -> * 80mm3 = 67.2 mg =  0.0
+20° - 0.9958 * 0.84 = 0.8364 -> * 80mm3 = 66.9 mg = -0.3
+30° - 0.9873 * 0.84 = 0.8293 -> * 80mm3 = 66.3 mg = -0.9
+40° - 0.9788 * 0.84 = 0.8221 -> * 80mm3 = 65.8 mg = -1.4

The usual fuel temperature should be in between -20° and +30°, where the properly tuned car will not allow you to to use the max IQ out of that range, so that 80mm3 from the example will be omitted if over.
The upper end over +30°C will be omitted, because if the fuel is over 30°C the the air I suspect will be for sure over 50-55°C and you`ll get all proper limiters kick in so we forget once again about that 80mm3 max IQ

Then in the regular range, you`ll get -10°where is 1.4mg difference. For +30°C you`re about -0.9mg below...
So here is my question : how "precise" you tune your cars? In micro grams so you get 0.3sec better result on the track?
What about the engine loses depending the engine temperature and environment, or that the owner will put fuel from fuel station XYZ and the fuel is.. crap?

I`m not professional in tuning, just like to read and test on my car.. So, my post is also just for the count :)))