Hello guys,

A got another doubt, in VagEDCSuite we have 3 types of smoke limiter, there are;

Smoke Limiter (x -> Mass Air Flow, y -> Rpm and the Z Axis with IQ)
IQ by MAF (this one is very similar (or equal) to the limiter above)
IQ by MAP (x -> Boost, y -> Rpm, z -> IQ)

I did the switch to MAP based SL (257 value on the switch) , put the max value in every cell of the IQ by MAF.

My question is, does the ECU still work with the Smoke Limit MAP, the first one???

How can i do a MAFLESS tune? Just by "unplugging" MAF type Map's (like IQ by MAF)?

To calculate the right IQ i'm using this formula: AFR = (Boost * cylinder capacitie) / IQ or in the right way Boost = (AFR * IQ) / Cylinder capacitie (in this case 474cc^3)

I'm letting the AFR to change from 15-16, boosting 2,5 Bar (Atm + Boost) with 77mg/stroke as max Injection.

Did the duration Maps, change the SOI axis to match the duration.

My tune is being limited like this;

IQ - DW -> SL -> TL

Boost - Boost target < Boost Limiter (Patm) < SVBL

EGR shut (850 all the way)

N75 stock, i know that this is awkward, the reason why is that i don't have (for the moment) VAG Com to do the LOGS and see what is happening with the way turbo are making boost.

Ecu did limp 1 time, when i was testing a map on a hill @200km/h and fourth gear, my SVBL is 2680mbar.


After i get this answer i will choose between MAF or MAP tune, and then do a 1,6bar map to run it on a drag event on the 6 of December.

With my previous Map i run 15.02s on the 1/4mile with Stock engine just Straight Pipe, and tune. (it was a "lean" tune AFR ~ 16 and 1,5Bar).

Thanks in advance. Cheers!!

Got some Answers already, in another Post.

For the guys that are trying to learn how to Mafless tune this is the way,

1 - Turn the Switch from MAF to MAP (need to find your own Switch location) and turn to MAP by putting 257 value on the Map, it should appear 0 (Value that switch to MAF type of Smoke limiter)

2 - On Smoke Limiter Map blanked with max value (don't need to do this just to set some piece of mind), on the IQ by Maf do he same thing (for the same reason...lol)

3 - Now do the math on your IQ by MAP (Axis: x -> Boost, y -> Rpm, Z -> IQ) using this formulas:

AFR = (Boost * cylinder capacitie) / IQ or Boost = (AFR * IQ) / Cylinder capacitie.

You should know that i'm using an Air Density of 1mg for each 1cc^3, so 474cc^3 will take 474mg of air (without boost).

So by boosting (for ex.) 2,5 (Atm. + Boost) Bar you will have 2,5 * 474 = 1137,6mg of air available if i want to run a 15,4 AFR the math is:

15,4 = 1137,6 / IQ, so IQ = 73,87mg per stroke.

That's the conclusion that i reach for now, anyone feel free to correct me.

Hope to help someone, Cheers!!
DavidRUCA

interesting calculation. i newbee to diesel tuning. would be nice to look at your map.

I didn't do the Update on this.. =/

The most correct AFR calculation that you can do is AFR = (Boost * Cylinder Capacitie * VE * AD) / IQ

AD - Refers to Air Density (You should see the average Air density in your region)
VE - Volumetric efficiency of your engine (mine 1.9PD Tdi begins @80% and near 5000rpm decreases to 75%

So, for example:

AFR = (2,5 * 474 * 1,17 * 0,8) / 66 this equals to an AFR of 16,8 (Smock-less).

Hope it helped.

can you help me
how convert boost map to MAF?

tks