Ed:

Thanks for the ideas and Figures.  I agree that having the diverter plate at the opening can cause lots of tubulance - expecially in climb. I have removed the plate and am waiting for the rain to quit so I can test fly it again.  If it is back to marginal but workable cooling I'll try another mod.
I'm interested in drawing on pictures and also sketching the duct so I can send more information to the group.  How do you draw on pictures?
I'm using Windows XP but don't have much experience with it.  Pictures of the inside of the duct have proven hard to take and show any good information.