Prop valve is right after the master cylinder. I have two lines coming out of the master -- one that goes to the backs, and one that comes out, "tees" and goes to teh fronts.

I put the prop valve in the engine bay because I figured it was one less thing the driver could screw up from the cockpit. Adjust in between sessions and leave it.

On the ducts and venturis...so if I narrow the duct down right before the rotors...I might increase the velocity of the flow and the efficiency of the cooling?? Neat idea.