"BTIZ" wrote in message news:Xmurd.164729$bk1.68505@fed1read05...
I remember that prop, but don't think it was for a MP increase.. I think it
was to slam more cooling air into the cowling..


From the website :

"On planes with the Wholey Cowl the SynchroPulse Flaps Increase
Manifold Pressure By Forcing Air Into The Engine Induction System -
It's Like
FREE SUPERCHARGING! "

The cowl is built so that the round intake hole is right behind the
tab in the prop.

John Galban=====N4BQ (PA28-180)