<HTML><FONT FACE=arial,helvetica><FONT SIZE=2 FAMILY="SANSSERIF" FACE="Arial" LANG="0">The 91 FX is stronger than the ys 91 4 cycle with some margin. Stretch the pipe a bit with an extra long header and run the larger prop. The set-up will amaze you with its output and quietness. Good friend Nat is using it on his X-Press turning a 17x10 N cut down 1/2 inch. Plenty of power for the 8-9 pound plane.<BR>
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Matt K<BR>
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<BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">Subj:<B>OS 91FX </B><BR>
Date:10/24/2003 12:50:40 PM Eastern Daylight Time<BR>
From:<A HREF="mailto:DGundling@compuserve.com">DGundling@compuserve.com</A><BR>
Reply-to:<A HREF="mailto:discussion@nsrca.org">discussion@nsrca.org</A><BR>
To:<A HREF="mailto:discussion@nsrca.org">discussion@nsrca.org</A><BR>
<I>Sent from the Internet </I><BR>
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What is the story on the 91FX. I have seen guys reporting<BR>
that they are running up to 15 inch props. Reports of running<BR>
a 14-10 are common. Is this with the muffler or is it obyained only with a<BR>
tuned pipe? The factory <BR>
recommended prop is something like a 13-8.On RC Universe there has<BR>
been a love/hate situation with the engine. Some report no troubles.<BR>
Others can't get it to run well<BR>
despite numerous efforts and parts changes. Is this thing as strong as a<BR>
YS91?<BR>
<BR>
Thanks.<BR>
<BR>
Dave </BLOCKQUOTE><BR>
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