Hello.
Found a good table to start from here: http://www.engineeringtoolbox.com/air-t ... d_771.html
Table is in lb/ft3, but you can multiply by 16.0184634 and you will have it in Kg/m3. You can look at 120F row (~49C).
Also, pressure is in PSI. You can multiply by 0.0689475729 and you will get bars.
10 PSI ~ 0.69 bar boost
20 PSI ~ 1.379 bar boost
30 PSI ~ 2 bar boost

MAF is reading air volume and ECU transforms that to air mass which will be used to calculate AFR`s. That`s the reason why MAF reading is corelated with IAT.

Now, i have a curiosity.
An engine that is running at 4000 rpm has 2000 strokes per minute or 120000 strokes per hour.
for an IQ of 35 mg/stroke that means 4200000 mg of fuel per hour (4.2kg). With an AFR of 17, it should have 4.2 * 17 Kg of air per hour which means 71.4 Kg/h, but that`s really wierd because the engine has readings of 380+ Kg/h at that rpm and that IQ.
Am I missing something?

MAF = MASS Air Flow meter. Not Volume. Mass corrected by IAT in ECU.
AFR by Smoke map this is limit for IQ by air, not for air.

I think you need to add "number of cylinders" in your formula, then;

4 cylinder X 4.2kg/h = 16.8 Kg/h

If MAF readings are 380 Kg/h, then your engine is running 21.4 AFR at 4000 rpm

Ok, so that's what i`m missing... each cylinder makes 2000 strokes per minute, not whole engine :)
@alex_sk, MAF is reading volume of air that is going though and volume is converted to mass inside ECU.
On one of my logs i have:
404Kg/h airflow
42 mg/stroke
4000 rpm
That means ~20 AFR so it makes sense why i have no smoke
With an AFR of 16.8 i can burn 50mg/stroke, so will make ~125 bhp instead of 106.
But my ecu in some way is limiting SOI to 5 degrees BTDC. Will be that enough to inject all diesel?

When calculating airmass dont forget to think about the EGR also ;) MAF is not measuring that.

Regarding your duration, check with the injector open times and calculate EOI.

EGR is deleted and even if was in place will have no effect at 3000+ rpm.

Is there a way to calculate MAP by MAF and IAT?

Also, i`ve read a lot of documentation regarding EOI and how to performance tune a car, but informations are pretty different from source to source.
Tested some stock softwares and almost everytime i`ve found values from 3 CA Gr to 9 CA Gr.

Also had a map with a lot of retard for testing and car smokes pretty bad.

Of course. You check the air density of wanted IAT, multiply it by MAF and multiply it by boost = MAP.

In practice; My BMW 530d has a cylinder of 487ccm3 in size, the VE is about 90% which means that about 438ccm is efficiently used. If you multiply this with air density of 1,165 (30°C) its 511,31mg/stroke of air. I know for a fact from datalogging that my intake gets about 505-515mg/stroke.

If you multiply this with my max absolute pressure (1 bar + boost) its 2,4 bar that goes around 1227mg/stroke. :)

EOI is a different story. I learned that theory and practice is two different things. Since i have a plan to do this on a dyno, i dont really sweat it with formulas. But in theory closer to 3°CaDEG will get your torque on.

I just calculate the EOI and adjust the SOI according to that so it's not factory retarded.

EOI has nothing to do with smoke, smoke maps do. Check your AFR's. In my experience from my BMW i kept the factory AFR or maybe a little bit richer mixture, there is no smoke at all.

xsashox wrote:In my experience from my BMW i kept the factory AFR or maybe a little bit richer mixture, there is no smoke at all.

Mondeo's ori WOT AFR is 20:1 to 22:1, I am currently running WOT AFR 16,2:1. That's a huge difference, but there's only light smoke noticeable, no dark clouds behind after turbo spool up. Still playing with timing to decrease it. :thumbup:

I am using a rearview camera to see what's coming ouf of an exhaust pipe :lol: Smoke is very obvious on light surfaces at lower speed - much more than looking at the rearview mirror. :thumbup: