I think his point was that if the maf sensor is in place then it is not used in load calculation. But if the maf sensor is removed then the 997t dme is capable of using map in load determination.

 

Are you sure about this and not speed density? Have you done a mafless tune on a 997TT? Alpha-N tunes would be pretty risky unless for a very specific application, like drag racing. The new 997.2TT does not use MAF. I don't know what they use for load but I would bet they are using MAP and speed density, not alpha-n.

 

So if you're using alpha-n, it's one specific set of maps based on rpm and throttle position. At WOT, things are pretty constant so you can set timing, fuel, etc...OK fine. However, alpha-n tunes do not take in consideration IATs. So what about non-wot situations, everyday driving? How do you tune for that? Do you have a summer tune vs a winter tune? As you know, there are many Proto cars running around with mafless tunes. Are you saying they are all alpha-n?

 

I would be very worried to run a tune that relies so heavily on knock sensors and wideband PID to constantly set timing and fuel. MAP pressure is also not taken into consideration with a pure alpha-n tune. Most alpha-n tunes, say in drag racing, run open loop. I just don't see how the rapid dynamic adjustments to timing and fuel could keep up in an efficient manner in a closed loop system that is running on alpha-n. This type of situation would be constantly increasing timing and then pulling timing. Same with fuel.

Agreed. Thanks for your input.

 

I run mafless tune since summer with no problems, is it unsafe for the engine?

 

Ask Proto what type of tune you are running for mafless, Speed-Density or Alpha-N. He wouldn't give you an unsafe tune.

 

Tony, I am correct you can trust me like i wrote you every turbo car equiped with ME7 ecu(include Porsches) can run with MAP sensor based load calculation, problem is to "teach" ecu to done that
And properly made mafless tune is a lot more safety for engine than normal tune on car with faulty or dirty MAF

 

With correct software inside ECU if the MAF is unpluged then its calculation and not correction, in same time load correction is from other factors like temperatures, altitude and etc...

The way you explain dont work true mafless, like i already wrote mafless tune is something different, its to tell ME7 to calculate load without MAF sensor but with MAP still conected, if you disconnect MAP too, then that complete different story and its something similar like to run stock car with stock ECU with MAF unpluged

 

If you do this, my prediction is the car will run fine the first time without the maf and then struggle a bit when you raise the boost (no maf). If you do this repeatedly the ecu will "learn" the new boost level and you would be good to go thereafter.