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Help with size of outboard for tunnel hull boat

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Help with size of outboard for tunnel hull boat

Old 03-19-2016, 09:01 AM
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Rangeley
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Default Help with size of outboard for tunnel hull boat

Hey all
I am building a tunnel hull from plans Dirk provided to me. Does anyone know how to determine engine size for this model. It is 26.5 inches long and I would like it to be able to go up to 50 mph. Can anyone help?

Thanks
Duane
Old 03-20-2016, 03:50 PM
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coriolan
 
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26.5" is a bit short but a .21 size engine(K&B or OS) would do if you can find one!
Old 03-21-2016, 06:10 PM
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ob nut
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26.5" is not short for a tunnel. That is a good size to run a .21, stock or mildly mod'd motor. With the speeds you are wanting, I'd try the O.S., either V1 or V2 would work.
Old 03-23-2016, 09:27 AM
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Rangeley
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Thanks guys - that's what I've been leaning toward. I talked with a girl at K&B yesterday, didn't get far there she was clueless - I was amazed!!
Old 03-23-2016, 02:19 PM
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ob nut
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MECOA is a joke with regards to K&B motors. IMHO: Hades will freeze before you see a complete OB motor come out from them. My Hot Shot Sprint w/K&B SS would radar at 44 all day long. I'm in the process of moving over to O.S. for my .21 motors. One of the SS's will be placed on a "play" boat. My racing boats will have the O.S..
Old 03-25-2016, 01:44 PM
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Rangeley
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Well that's done! I ordered the O.S 21 outboard this morning. Now I have another question - it appears to me that the pull/pull steering setup would be the smoothest operation option ...........your thoughts please guys?
Old 03-25-2016, 07:03 PM
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ob nut
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The 4-40 rod / colars are the easiest to setup for steering. For my new setups, I'm switching all the steering to pull-pull. Hangar9 pull-pull wheel, Secraft wire tensioners and kevlar cord.




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