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<DIV>I could be wrong but it is my understanding the machined type heads are
made from bar stock, not die cast material. The greater density of the bar
stock material should transfer heat more efficiently than a die cast piece. It
is true in racing applications one used to polish the piston tops and combustion
chamber to aid in maintaining heat in the combustion chamber ( now there are
coating for this ) as well as ward off carbon deposit build up. I think
the difference is the ability for a given material to absorb and transfer heat
versus the way a surface finish radiates heat. </DIV>
<DIV>Ed M.</DIV>
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style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=burtona@bellsouth.net href="mailto:burtona@bellsouth.net">Dave
Burton</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=nsrca-discussion@lists.nsrca.org
href="mailto:nsrca-discussion@lists.nsrca.org">NSRCA Mailing List</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Monday, March 06, 2006 5:49
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [NSRCA-discussion] OS Shadel
piston/liner</DIV>
<DIV><BR></DIV>
<DIV><SPAN class=694424422-06032006><FONT face=Arial color=#0000ff size=2>I'm
curious too Bill. Then same material should have the same heat
characteristics. Surface irregularities from casting should have more
effective surface area for greater heat loss.</FONT></SPAN></DIV>
<DIV><SPAN class=694424422-06032006><FONT face=Arial color=#0000ff size=2>Of
course my thermo and metallurgy courses were a long time
ago.</FONT></SPAN></DIV>
<DIV><SPAN class=694424422-06032006><FONT face=Arial color=#0000ff size=2>Dave
Burton</FONT></SPAN></DIV>
<BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B> <A
href="mailto:nsrca-discussion-bounces@lists.nsrca.org">nsrca-discussion-bounces@lists.nsrca.org</A>
[mailto:nsrca-discussion-bounces@lists.nsrca.org]<B>On Behalf Of </B>Bill
Glaze<BR><B>Sent:</B> Monday, March 06, 2006 4:42 PM<BR><B>To:</B> NSRCA
Mailing List<BR><B>Subject:</B> Re: [NSRCA-discussion] OS Shadel
piston/liner<BR><BR></FONT></DIV>
<DIV><FONT face=Arial>Ed:</FONT></DIV>
<DIV><FONT face=Arial>Just wondered why the machined head would show better
heat dissipation. We were always taught that an as-cast surface showed
better heat dissipation because of the greater developed surface area.
In fact, the "bad example" was the buffed and polished surface. It
showed terrible heat characteristics. (Unless, of course, you were
looking for heat retention.) The above assumes, of course, that the
materials involved were similar or exactly the same. Not quarreling,
just curious. </FONT></DIV>
<DIV><FONT face=Arial>Bill Glaze</FONT></DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=edbon85@charter.net href="mailto:edbon85@charter.net">Ed
Miller</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=nsrca-discussion@lists.nsrca.org
href="mailto:nsrca-discussion@lists.nsrca.org">NSRCA Mailing List</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Monday, March 06, 2006 4:14
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [NSRCA-discussion] OS
Shadel piston/liner</DIV>
<DIV><BR></DIV>
<DIV>I'm not sure how one plug going out would cause the engine to go
lean. At best having 2 plugs would cause the point of combustion to
be a bit earlier OR ( what I believe ) would cause a slightly more
efficient burn of the compressed air fuel mixture. Having 2 plugs also may
ward off a sudden engine failure due to a blown glow plug. The real
advantage in my book of the Mintor head is it is made from bar stock, not
cast and therefore has a better thermal efficiency, it sheds the head of
combustion quicker and better than the cast head. The lighter weight
and second plug which may improve mid range are just a bonus. If I
look back at older OS and YS engines, the more "high performance" versions
of the same engine had machined bar stock heads. For example the YS61AR
and the YS 61R, the AR having besides other improvements a machined bar
stock head versus the 61R die cast head. </DIV>
<DIV>Ed M.</DIV>
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style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=pattern4u@comcast.net href="mailto:pattern4u@comcast.net">Grow
Pattern</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=nsrca-discussion@lists.nsrca.org
href="mailto:nsrca-discussion@lists.nsrca.org">NSRCA Mailing List</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Monday, March 06, 2006 10:42
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [NSRCA-discussion] OS
Shadel piston/liner</DIV>
<DIV><BR></DIV>
<DIV><FONT face=Arial size=2>Randy,</FONT></DIV>
<DIV><FONT face=Arial
size=2>
Said another way, if you lose a plug on a twin head, the engine goes
lean and usually get very hot :-( </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Learned that one the hard way. Using two
plugs to fix a rich spot transition on a pipe IMHO is at best a
band-aid. Try it and see for yourself :-)</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Eric.</FONT></DIV>
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style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=d.pappas@kodeos.com href="mailto:d.pappas@kodeos.com">Dean
Pappas</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=randy10926@comtekmail.com
href="mailto:randy10926@comtekmail.com">randy10926@comtekmail.com</A>
; <A title=nsrca-discussion@lists.nsrca.org
href="mailto:nsrca-discussion@lists.nsrca.org">NSRCA Mailing List</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Monday, March 06, 2006
10:31 AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [NSRCA-discussion]
OS Shadel piston/liner</DIV>
<DIV><BR></DIV>
<DIV><SPAN class=078432915-06032006><FONT face=Arial color=#0000ff
size=2>Hi Randy,</FONT></SPAN></DIV>
<DIV><SPAN class=078432915-06032006><FONT face=Arial color=#0000ff
size=2>Mintor parts are available from Aeroslave. </FONT></SPAN></DIV>
<DIV><SPAN class=078432915-06032006><FONT face=Arial color=#0000ff
size=2>I find that the twin plug head is not absolutely necessary, but
it widens the nneedle valve sweet-spot: in the rich
direction.</FONT></SPAN></DIV>
<DIV><SPAN class=078432915-06032006><FONT face=Arial color=#0000ff
size=2>Dean</FONT></SPAN></DIV>
<DIV> </DIV>
<P><FONT face="Times New Roman">Dean Pappas</FONT> <BR><FONT
face="Times New Roman">Sr. Design Engineer</FONT> <BR><FONT
face="Times New Roman">Kodeos Communications</FONT> <BR><FONT
face="Times New Roman">111 Corporate Blvd.</FONT> <BR><FONT
face="Times New Roman">South Plainfield, N.J. 07080</FONT> <BR><FONT
face="Times New Roman">(908) 222-7817 phone</FONT> <BR><FONT
face="Times New Roman">(908) 222-2392 fax</FONT> <BR><FONT
face="Times New Roman"><A
href="mailto:d.pappas@kodeos.com">d.pappas@kodeos.com</A></FONT> </P>
<BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B> <A
href="mailto:nsrca-discussion-bounces@lists.nsrca.org">nsrca-discussion-bounces@lists.nsrca.org</A>
[mailto:nsrca-discussion-bounces@lists.nsrca.org]<B>On Behalf Of
</B>Glenn Hatfield<BR><B>Sent:</B> Monday, March 06, 2006 9:23
AM<BR><B>To:</B> nsrca-discussion@lists.nsrca.org<BR><B>Subject:</B>
Re: [NSRCA-discussion] OS Shadel piston/liner<BR><BR></FONT></DIV>
<DIV style="FONT-FAMILY: Arial,sans-serif">
<DIV>Where do you get the mintor head?</DIV>
<DIV> </DIV>
<DIV>Does the dual plug really help any?</DIV>
<DIV> </DIV>
<DIV>Randy</DIV>
<DIV><BR><BR>--- ronlock@comcast.net wrote:<BR><BR>From: "Ron
Lockhart" <ronlock@comcast.net><BR>To: "NSRCA Mailing List"
<nsrca-discussion@lists.nsrca.org><BR>Subject: Re:
[NSRCA-discussion] OS Shadel piston/liner<BR>Date: Fri, 3 Mar 2006
17:37:30 -0500<BR><BR></DIV>
<DIV><FONT face=Arial size=2><A
href="http://www.pspec.com/">http://www.pspec.com/</A></FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Ron Lockhart</FONT></DIV>
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