Did yet more screwing around with the T04E 50 trim map and came up with the below.

There are now two new points and a plot as well.

• The yellow point represents a boost ceiling of 24psi and 86% VE.
  
• The blue point is 26psi and 86% VE.
  
• The light blue area represents an efficiency range of 76%.
  
• The green area is 78%!
  

The plot is a very wild and generous guess of where I would be in terms of efficiency at various points in the rev range starting at 2500 and going to 6200 RPM for a redblock. That plot suggests that the unit spools relatively quickly but that's something I really have no idea of until the unit is on the car and spinning. There are others running very similar setups but I yet have no data from someone running the same Cosworth hotside / T04E combo that we are talking about here.

Another thing about that plot line is it's suggestion or hint that if I spool faster then the guesses I've made, I could well be into surge land. Let's hope tat's not the case.

I just can believe how good of a setup these T04E 50 trim units are. Look at the size or combined areas of the 78% and 76% regions. That's absolutely huge!