<snip>

To all on the list, and especially Ed Anderson:
I am certainly of the belief that one good test is worth 1000 expert
opinions. Ed, you seem to have success with plugs up, and that is why my
skepticism is tempered. I don't know that plugs up will necessarily

cause the

problems that I have raised. I firmly believe that at some installation

angle

those problems will arise, but perhaps plugs up is just not far enough.

My

main reason for the post was to indicate that the motion of the oil

*within*

the rotor itself has little to do with gravity, accelerations, or engine
orientation.

I agree whole heartedly with this.

However, once the oil exits the rotor into the oil drains,
gravity, accelerations and engine orientation have everything to do with

oil

scavenging.

This I also agree with. That is why I would prefer to use a dry sump system
with a plugs up engine. If you place three oil pick-ups in the engine, one
for each rotor, and one for the pressure regulators and front cover, you
solve this problem. If you are going to go plugs up and use a turbo, you
need the scavenge pump anyway, so why not just go ahead and use the dry sump
system. You can then scavenge the gearbox as well and prevent pressure build
up and seal leakage.

Your experience seems to indicate that plugs up is OK from this
point of view, but certainly you are closer to the "edge" running plugs

up

than you would be in a conventional installation. We just don't know

where

the "edge" really is....

Jon Lauter

That being said, it adds a lot of expense, weight and extra work. The only
reason that I considered it was that it fits my pusher installation very
well if I used a turbo. The exahust and intake are right where I need them.

There is still the problem of air bubbles being trapped on the high side of
the engine near the spark plugs. You could add some bleeds here to take care
of this problem. I still maintain that If your cooling system is functioning
properly with the right pressure, and enough cooling capacity that there
should not be any steam pockets in this location.

Monty

Where do you plan to put the radiator(s) Monty?
Send us one of these fancy pictures showing us the under the cowl layout :-)
I would settle for just a three view.

Paul Lamar
 
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