Sender: <marv@lancaironline.net> (Marvin Kaye)
To: lml
Date: Wed, 11 Sep 2002 00:18:27 -0400
Message-ID: <redirect-1730566@logan.com>
From: MattHapgood@carolina.rr.com
Subject: Re: [LML] LNC2 Filter / Ram Air Valve

Larry and others...

I have a question about the ram air design you and others 
(including factory Mooney's) use.  If you pick up 
sand/dirt/rocks while running filter air, won't they just 
sit in front of your valve (inside bottom of the scat 
hose)?  Then wouldn't it just get sucked into the engine 
when you open the valve to ram air?  I have spent a lot of 
time noodling how to keep something like that from 
occuring - namely putting the valve at the VERY front of 
the cowl to where it would actually fair into the front 
cowl.  But this is a tremendous amount of work.  Or putting 
a small hole in front of and below the valve to let 
dirt/debris "drop" out (but then losing ram...)?  Am I 
making a mountain of a molehill????

Matt

> Some time ago I was asked for a photo of my Y valve used 
for Filtered vs
> Ram air.  Attached are two photos.  You'll notice it had 
to be very
> tight to fit into my cowl.  This prototype has one major 
flaw.  While
> running exclusively RAM airflow, it backwashes the 
filter.  This slight
> pressure loss is only relevant while racing.