www.iFourWinns.com

Hi everyone.

I'm looking for some opinions on what size motor I need on my 2010 Grand 310 (10ft) RIB to get it to plane with 2 people (approx. 370lbs). I'd like go with a 4 stroke Mercury but I'm unsure of what HP.
One dealer tells me 9.9 and the next says 15

Anyone had some past experience with this?

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"ROCKHOUND"
2005 Vista 298
Georgian Bay, Ontario.

A 10hp 4 stroke will plane out with 2 people in a 10ft rib. You may have to put a bunch of weight on the bow to get up - but it'll get there.

If the 15hp weighs the same as the 10hp, and your boat is rated for it -- bigger never hurts.

That being said, I have a 10ft achilles with a 2.5 yamaha. I put around nicely, but there's definitely no planing going on.

A good friend with an 8hp 2 stroke yamaha and a 9 foot air floor inflatable planes out with 2 adults and a small child -- but 2 beefy adults, not so much.

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2008 318 Vista -SOLD, but I am still around!
All Night Long, Seattle WA

You can never have enought power... so I figure one of those new Optimax 150's would be about right - should get it up on the plane in less than a second!!

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Alec

2006 Horizon 190
VP 4.3GL/SX, Sunsport

Also consider adding some tabs. I put a set on our dinghy and it made a heck of a difference in the time it takes to get up on plane. We've got a 9ft inflatable with a 9hp 2-stroke. Without the tabs it pretty much would not plane with two people without a lot of weight forward and some patience. And even then it'd have to be on glass-smooth water. Now it'll pop up within seconds. But you do have to watch out, it can get mighty twitchy to control when going faster.

The main benefit to the tabs (the cheap folding ones from WM) is they extend a flat area from the transom to back under the points of the side sponsons. This keeps them from 'digging in' as you start accelerating. For a RIB you'd probably want better tabs than these. But I don't know which ones.

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-Bill Kearney, 2005 348 Vista

I have a 2.8 m RIB with a 4 stroke 9.9 Merc planes with 3, 2 easy, i have put wings on the cavitation plate this hepls to lift the rear.

I would say a 15Hp would be the best for yours

Cheers

Sean

Thanks all for the advise... I think I'm going to go for the 15hp.

Cheers

Pete

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"ROCKHOUND"
2005 Vista 298
Georgian Bay, Ontario.