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mfc
10/04/2016, 16:21
Bonjour à tous

I think that can be useful to compare the efficiencies of different intercooler types by measuring the quantity of air which enter in the cylinder on every stroke instead of comparing directly the flux in g/s measured by the MAF.

To do this type of measurement:
Using the OBD2 interface, record at least the PIDs 0x0C (RPM) and 0x10 (MAF)

And then use the following formula
For any 4 stroke 4 cylinders engine: mass of air in the cylinder (g)=MAF (g/s)*30000/RPM
For example, with 155.11g/s and 4900RPM, I get about 950g

If you record from the OBD2 interface the PID 0x34 (lambda sensor), you can even calculate the quantity of the fuel injected into the cylinder.

For the comparison can be useful to record the intake air temperature (PID 0x0F) and the boost pressure (PID 0x0B)

Anyone that want to participate, posting tabular or plotted data and some info about the car setup, is welcome!

Best Regards
Marco

pichnaute
10/04/2016, 23:52
Hello mfc
Nice to meet you again
So, you would like too compare, some intercooler on the ep6 ?
For me you must to know intercooler pressur drop, and air intake manifold pressur and temperature for a same mass air flow, between different intercooler.
I think more People don t know PID, even use obd2 !
I am very interesting about your question, and for sure i follow your topic...

tedenx
17/04/2016, 00:55
Hi and sorry for the late answer.
I think it's a better idéa to compare the loss of pressure between the both intercooler .
Maybe Shado666 can say to us the value to his manifold air pressure to compare with me.
We have the same map in stage 2 but not the same intercooler.
If we do That, we have to choose the same concept of test like à 50-150 km/h no ?