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Old 03 July 2007, 10:30   #11
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Twin 55hp?

About 10 years my old boss had an ex RNLI Atlantic 21 with twin 2 cylinder Evinrudes (also ex RNLI) 50hp or 55hp I think. Made 32 knots on our GPS if I remember. Seemed plenty of power at the time!

I think that the 1 ton displacement is about correct but might also include the engines - those twin cylinder Evinrudes must be pretty light! No power trim - so even lighter.

Hope this helps.
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Old 03 July 2007, 13:48   #12
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If you're set on twins, what about a pair of 75 e-tecs?

Personally, I'd also fit an aux. alongside a large single, which gives a lot more power for your money, but you may have genuine reasons for a twin set-up?
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Old 03 July 2007, 14:57   #13
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Originally Posted by Doug Stormforce View Post
Is 25kg on the back of a 1 tonne boat going to really stop it getting on the plane? Not trying to argue, this is the sort of discussion/opinions I want to hear.
Probably not! The lack of initial acceleration that you get with a 2 stroke might make a difference though.(bigfoots might help?) The extra weight is just another factor against.
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Dont however agree with your club safetyboat idea, it is a wholly inappropriate boat to put in the hands of a volunteer safetyboat driver at a club.
Fair comment.
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Old 03 July 2007, 15:28   #14
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Doug,

I did a sea trial on an old parker (thundersomething) 630 a few years ago which had twin mariner 60 four strokes.

Wide open in a short chop in Poole harbour best we could get was 31 kts. really struggled with just one engine as you would expect.

The rib was fairly heavy in its layup although no idea how the weight would compare with the Atlantic.

Cheers
Howard.
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Old 06 July 2007, 06:08   #15
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Atlantic 21

Thanks for all of you discussion / help and advice.

I think the twin etec 75s solution was sounding quite good, however its all now become academic as the boat has just sold.
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Old 06 July 2007, 16:47   #16
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