<VV> valve seats revisited (Engine Braking)

[RoboMan91324 at aol.com]

Joel,
 
That makes sense with a non-running engine.  With the  plugs in, the energy 
it takes to compress the contents of the cylinders on the  compression 
stroke is regained when those compressed contents force the piston  back down on 
the power stroke.  With the plugs out, the compressed gasses  escape 
through the relatively small plug hole on the compression stroke and then  suck in 
through the hole on the power stroke.  In the first case, energy is  
conserved in the repeated compression-decompression cycles but in the second  
case, you are pumping air in and out repeatedly.  Each stroke results in an  
energy loss.
 
Doc
 
1960 Corvette, 1961 Rampside, 1962 Rampside, 1964 Spyder  coupe, 1965 
Greenbrier, 1966 Canadian Corsa turbo coupe, 1967 Nova SS, 1968  Camaro ragtop

~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
In a message dated 5/8/2012 12:28:21 P.M. Pacific Daylight Time,  
virtualvairs-request at corvair.org writes:

Message:  5
Date: Tue, 08 May 2012 12:38:37 -0500
From: Joel McGregor  <joel at joelsplace.com>
Subject: Re: <VV> valve seats  revisited  (Engine Braking)
To: "virtualvairs at corvair.org"  <virtualvairs at corvair.org>
Message-ID:
<D522952017BFA547BC2D93BEBA6A3BE3EAF9ACFB8C at W2K8SBS.joelsplace.local>
Content-Type:  text/plain; charset=us-ascii

It takes more power to spin a non-running  engine at a significant RPM with 
the plugs out than with the plugs in.
Info  Smokey found when measuring engine friction losses at speed.
Joel  McGregor