I too think the Gen-turi is a great idea, expecially when camping close quarters at rallies. I was at a FMCA rally when a neighbor coach purchased one at the rally and had it installed on site. The installer demonstrated the venturi effect by tearing a (very) small piece of paper and letting it go down at the bottom between the small pipe and the large pipe. That piece of paper shot out of the top within a fraction of a second (thus the ventur effect, speeding up the gasses between the small pipe and the large pipe).
For you folks who build your own, make sure it's not an exhaust extension, but truly creates a venturi effect.
I wouldn't be without one at a rally insuring good neighbor policy.
P.S. I bought one to make sure I didn't screw up the design.
'07 Winnebago Journey 34H - CAT C7, Koni's, MCU's, SS Bell Crank, Safe-T-Plus
'07 HHR Toad, SMI AFO, Blue OX