NefMoto

Hey all,

I've been going through the SIMOS FR (much appreciate nyet) and bin file, and it seems to me there is a hard limit of 1389mg/stk in the software.  Which is around 550 crank tq.  The Aircharge to Torque map is one of many examples.

From best I can tell, SIMOS 8.4/8.5 are largely based on earlier SIMOS versions for the Audi 3.2fsi which used a MAF primarily, and speed density for transient calculations as many OEMs do.  I think the 1389mg/stk was a limitation of MAF readings, you can google the number and other platforms have an identical limit.

But when Audi moved completely to speed density, they kept this limit.  The MAP side seems fine with physical limits of 5434 hPa.  But the speed density calculation seems like it has a physical limit defined at 1389 mg/stk

If Torque was limited, it would be less of an issue since Torque isn't measure directly but DEFINED by airmass.  Airmass however is calculated directly off of MAP sensors.

This limit probably won't be hit with the tvs1320, but I want to go big turbo this summer if possible.  

Am I missing something?  This is the first ECU i've ever looked at.  

You are not missing anything.
You will need to underscale the load calculated and then overscale the load -> torque conversion with this ECU.
On newer ECU's they doubled the range.

Also, these ECU's will hard reset once you hit >1023.9nm calculated.

Shit.  And since we don't have fueling tables but calculated fueling from target lambda and airmass, our fueling now needs to be scaled in the inverse of airmass scaling, right?  

What new ECUs double this limit?  Simos 16?  I see the 3.0T EVO uses that ECU, would swapping to that ECU likely be an easier thing to pull off ?  That would also come with the added benefit of port injection.

I have not looked at S16 differences.
I don't see what the big fuss is about though.

Scale down the calculated load.
Scale up the calculated torque
Scale up the fueling through inversing the load scaledown in fuel correction maps.
Rescale the ignition map load axis, again inversing the load scaledown.

I don't imagine you're gonna run superduper boost, and I don't think 30% will be too bad.

I can add full RAM logging to S8.4/8.5 in my logger to make the job easier.

Btw, the torque is only really important if you're running DSG or 8HP.
In case you're not, then forget the TQ, just scale your load and rescale ign/fuel and you're good.
Although if you ARE running DSG then... lol... you're in for a world of hurt once you exceed 800nm.

Once you hit such limits, it's all spreadsheets in a box. Garbage in, garbage out.

I assumed we would need to edit the underlying speed density equations and everything it references. 

Which logging tool do you use that displays all of this?

very interesting thread.
Im doing big turbo conversion on my 3.0tfsi paired with zf8hp.
Any news on author project?

I was going to try rescaling, but then realized fuel pressure is also limited at 174 BAR.   I think I might try rescaling both over winter.