Ed,
DIE at one single RPM is exactly what I want.  The target RPM would be what I get at something less than WOT at cruise altitude.  Perhaps if that was close to T/O RPM I would shoot for a "dual purpose" RPM, but cruise is my objective.  Takeoff should not be a major consideration since if I can get anywhere near the cruise I want, I can take off (at airports where I will operate) with room to spare.

If turbo rotor housings are ported symmetrically, how far off that would NA housings be?  Would "street porting" bring the path lengths (in the block) closer together?  If so, it might be possible to close the gap between primary and secondary paths in the block so as to merge  them into a single runner and retain some DIE effect.  Is it possible that DIE might be enhanced if the closing of one port was a little later than the closing of the other?  Probably too much to ask.  I guess I'll understand a lot better when I get my engine torn down and get a look at the porting.

It would be great to simplify the intake though ... Jim S.

Ed Anderson wrote:

 I believe (but have no data to support the belief) that if you want the DIE effect at only one rpm, then given all else is equal (which it seldom is) then it may make sense to port an engine to give the same timing on both primary and secondary.  I think this would be hard (and not necessarily good) to do on the 6 port as there is a wide difference between say the secondary and aux timing.  I think it is easier to get the two ports on a turbo block equal in timing without major challenges. I will be merging my primary and secondary runners shortly after they exit the engine block on my next manifold.  My ports are already equal in timing.  So hopefully with in the next month or two, I will have this new intake fabricated and can provide some data on the results.