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<DIV>I've had some success with the O-ring setup. I had one plane with
fixed header and the other with O-ring and started with a bad attitude about the
O-rings. I have since switched both to Oring setups. Once I figured
out the secret to getting long life from the O-rings I find the vibration
reduction, stress reduction, weight reduction all positives. I wrote a KF
article on this that will probably show up in the next issue but basically you
don't want to remove the header from the O-rings until replacement time.
Remove the adapter from the engine just like a fixed header. Also,
stabilize the coupler firmly. My mintor has had the same O-rings in it
since May or June with no leakage.</DIV>
<DIV>--Lance</DIV>
<DIV> </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=AtwoodDon@aol.com
href="mailto:AtwoodDon@aol.com">AtwoodDon@aol.com</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=ed_alt@hotmail.com
href="mailto:ed_alt@hotmail.com">ed_alt@hotmail.com</A> ; <A
title=discussion@nsrca.org
href="mailto:discussion@nsrca.org">discussion@nsrca.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Saturday, October 08, 2005 8:34
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [SPAM] OS 1.40 header</DIV>
<DIV><BR></DIV><FONT id=role_document face=Arial color=#000000 size=2>
<DIV>
<DIV>Ed, I observed the same thing about the OS header flange not matching the
exhaust port so I ground it out to match the engine but did not observe any
improvement in performance. I have switched to the Macs header because
of the O-ring wear issue. I did like the isolation of the engine from
the header by allowing it to pivot on the rings but you always know it is time
to change the o-rings when you start getting some blow by. </DIV>
<DIV> </DIV>
<DIV>There was some short comment about a better way to support the OS type
header and increase the o-ring life (I think it was here on the discussion
group) some time back but I can't remember who it was.</DIV>
<DIV> </DIV>
<DIV>Don</DIV>
<DIV> </DIV>
<DIV>Don AtwoodIn a message dated 10/7/2005 7:17:39 P.M. Pacific Daylight
Time, ed_alt@hotmail.com writes:</DIV>
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style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size=2>
<DIV>Just wondering what the opinions are re. the best header for the OS
1.40. I've got the OS version and it's a bit of a nuisance to deal
with the O-ring going bad. Also, it really looks like it would result in
improved gas flow (more power) if the inlet for the "matched" header was the
same size and shape as the exhaust port. I'm tempted to grind it down
to get that match right. Has anyone done this and does it help?</DIV>
<DIV>Thanks</DIV>
<DIV> </DIV>
<DIV>Ed </DIV></FONT></BLOCKQUOTE></DIV>
<DIV></DIV>
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