I made a series of videos of muffler.  It was easier than trying to explain in an email.

I've not taken any measurements yet, but subjectively I think it's working well.  Even after I turned the injectors around, fuel is still pooling in the intake manifold.  I've got a more drastic fix curing right now, so I might have valid numbers in a couple days.

http://www.youtube.com/watch?v=n7m6t8ZnUT4

http://www.youtube.com/watch?v=3aUivLupypE

http://www.youtube.com/watch?v=CFEO_DEkOWY

http://www.youtube.com/watch?v=KPQclfSK4DI