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Old 28-12-2009, 10:08 PM   #1
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Fountain 42 Drives

OK, Stern drives are newish to me, we are running XR with speedmasters & hering 6 blade props, we started at 33 pitch @ 91mph. We now use 34's @ 96mph but the motor's are still on the rev limiter. We could buy 35's but does anybody know what would happen if we dropped the drives 1/2 inch, I know the revs would go down but would we go any faster or better acceleration...

Any comments??
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Old 29-12-2009, 03:26 AM   #2
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Remove the rev limiters and let em sing. Lowering the drives will bring the RPM down some but also the speed with it. The drives are high on the Fountains but the hull is design to work with it and they deliver very good speed for the HP. When I was on your boat the drives didn't seem overly high, the boat was very trim able. You might see if someone can redo your props adding some pitch or cup to the trailing edge.
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Old 29-12-2009, 02:32 PM   #3
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Not that your having performance related engine issues already as your engines are hitting the limiter, but this thread is interesting if you have 600sci it goes on to says a stock 600sci made 579-581hp at 5400rpm and after a few mods it reached 700hp at 5850rpm ... if your running the 600's that little mod with some new props would probably see 100+mph

http://www.offshoreonly.com/forums/g...mentation.html

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Old 29-12-2009, 03:36 PM   #4
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CFUN

Thanks for the thread

I will have a look at getting the RPM lifted to 5700-5800

That should be enough to max out the current props

98mph'ish is fast enough for me!!

Great thread on offshore only though!!
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Old 29-12-2009, 11:56 PM   #5
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I got some 36's.
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Old 30-12-2009, 07:43 AM   #6
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What are you? Some kind'a international Propeller trader?
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