NefMoto

Hello, just have an idea. First 2ltr 147kw TFSI engines have higher(on paper) consumption than newer 2.0 TSI 155kw engines. One of main changes is higher fuel pressure(110bar to 150bar, the peak values). So did anybody try tries to set higher pressure(as much as possible,even use RS4 prv) in cruise rpm/load area on TFSI engines + compensate to correct lambda , to reach better MPG ?

The amount of ignorance in this sentence baffles me.
Not only do you not understand engines, you do not understand mixture control in MED9.

Short answer - NO POINT. As to why, do some reading.

I tried to be humble, so i put my question to Noob section..... no matter, i was burned to hell anyway :(

I asked if anybody tried it in real. Your confidence is from teoretical knowledge only, so ok its probably obvious fact = you dont wasted time by doing it. Are you willing to point me where i can read it?

And you deserved it bigtime, because you spout crap like this:
Without having any idea about my background.

I answered your question. Pick up a book about engines and EFI and read the basics.
And then open the MED9 FR and read how IPW is calculated. Not my fault if you are lazy and want everything served to you on a silver platter instead of doing some reading.

You are talking about MED9 147kKW and MED17 155KW engine? These engines are completely different hardware, open the engine hood and you see it immediately. It´s EA113 and EA888...

PRJ: i expect you pick only "negative" what i wrote. It was writed and meaned only strictly to rise pressure inside cruising condition, nothing else. Sorry if i make you angry about that, i probably wrote it bit akward.

Cherry: of course, i pick the "difference" between them, which can be changed on the older one. As engineers have an reason why rised the pressure, but i asked in the end, if its to lower MPG or for something else.
 

I already told you that pressure has no direct correlation with fuel efficiency.
If you do not understand why, then read about DI systems and how/why pressure is set in the first place.

I'll give you a hint - it is to do with IPW / injection duration / optimal angle.
By blindly increasing pressure in cruise area you will always worsen fuel consumption.

If fuel pressure magically increased fuel economy, why wouldn't everyone just increase fuel pressure until all cars magically had infinite fuel economy?

Where did you get the idea that increasing fuel pressure would give you better fuel economy? What mechanism would give this result?

More pressure more better?

I'm going to guess maybe he thought higher pressure = better injector atomization = more power with less fuel.

atomization is a complex thing; the trick isn't more or less pressure, but the right pressure.

Agree. It's not just the pressure, but everything else involved between that pressure and the cylinder. Just guessing his train of thought.