Here is the map cleaned up a bit. I was able to interpolate the data to get the efficiency islands made with a good amount of certaintly.
I know you need to know the VE of the N54 amongst other things to get really correct calculations, but if you just work on a VE of 90% you can see some of the PRs obtained with the tunes that the turbo is going WAY outside the map. Shaft speeds must go thru the roof when trying to hit higher boost levels in the upper RPMs. No wonder power tapers of so much on the dynos you see.
