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Bruce
 
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Default prop pitch/rpm and trim?

Your underproped


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Bruce
99 White WJ 4x4 Select Trac
89 YJ
03 Liberty Ltd L.O.S.T #000256
90 XJ6 Sovereign

"werlax" wrote in message
om...
I was on the lake tonight and doing some RPM testing and something
doesn't seem right. The lake was calm and I've got a 4.3L 190HP
Mercruiser on an 18' bowrider (about 2500lbs). The engine is rated at
4400-4800 RPM. The prop is a 14x23P. The literature states that the
boat should hit about 52MPH. Granted, the gauge on the boat might not
be entirely accurate, but I was only able to get about 45MPH running
pretty close to 5000 RPM. I was trying to modify the trim, but mostly
was running about in the middle (if that means much to anyone) - trim
level. I am going to do some more testing, but my initial thoughts
are that I need to go up one degree? To a 24? Is there something
that I could be doing wrong to get these results?
Thanks for any help!