| He is moving the essentially the same airmass as Dee and I are at 6500RPM where we are all making the same power (66xRWHP), which suggests identical VE. Looking at the plot of boost vs. RPM, you can see that we are all three making the about the same boost level at 6500RPM, which is the maximum capacity of the compressor at that RPM level: ~26psi. Seb's car is only achieving 24psi, so he is making the same power at slightly less boost which suggests higher VE at this RPM only. 
This has been my qualm with the use of the term "VE" in this discussion, is that the true definition of VE refers to the cylinder filling capability of the engine over its operating range of engine RPMs. VE is a dynamic metric, not a single point value. Additionally, we are all three making about the same boost level when we are all making the same power level. Seb's car does not have higher VE at 3000RPM, 4000RPM, 5000RPM, or even at 6000RPM, else, he would be producing more power than Dee and I. In fact, this is exactly the opposite of what is observed in the dynocharts. It isn't until about 6500RPM that his VE has caught up to Dee's and my own. We all three have the same VE at 6500RPM, meaning, we are all three filling the cylinders with the same quantity of airmass. Seb's setup does not have a higher VE - it is more/less the same as the other two at 6500RPM and significantly compromised before that RPM due to the turbine and housing selection he is using. Seb may be producing 66xRWHP at 2psi less than Dee and myself, which could be construed as having a higher VE, which I will agree with, however, if this is the maximum boost he can achieve where Dee and I can achieve higher, wouldn't using the term VE make a moot point, especially considering the severely impacted VE at RPMs lower than 6500RPM? My question is, when one uses the term "VE" here, are they meaning VE of just the engine itself, VE of the entire system, or VE contribution of the turbo? If we look at it purely from a massflow standpoint, all three of these cars are moving the same amount of air mass at 6500RPM. Dee's setup has more area under the curve than Seb, and I have more area under the curve than both of them. Bottom line, Seb's car produces less boost specifically because of the turbine housing he is using, which is a far simpler explanation to use than to say his setup has higher VE, which with all things considered, could be correct or incorrect dependent on your definition of it.
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