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Old 19-12-2009, 09:43 AM   #21
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Country: England
Location: West Sussex
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Boat name: OVERLORD
Boat make: RING 34' SPORTSBOAT 2 X V8 PETROL
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Quote:
Originally Posted by Jon Fuller View Post
Mike's designs do seem to need shed loads of bow lift to get the best top end out of them. When TD and I raced the 26, I never stopped being amazed just how how much it needed / would take. If we set the trim to it's max speed position, whilst on the trailer, when you looked at the drive, it seemed inconceivable that it could be the most efficient angle, as the drive was virtually trimmed right out of the wear cheeks on the gimble. quite extraordinary.

Was never much fun, running close to 80 in calm conditions, trimmed like that, then finding one wave bigger than the rest. Could feel a little 'loose'.
If it aint 'Twitchy' it aint moving !!

I like it 'Unstuck'

Anyway , as with the stepped Rings of the late 70s and early eighties, newer and larger but stepped designs have a different angle of attack.
Over the counter power has increased considerably in the last few years as has the weight of that power and this has made a lot of earlier sportsboat designs unsuitable for the heavier motors unless the Cof G is shifted.

Mike
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Old 19-12-2009, 11:01 AM   #22
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Quote:
Originally Posted by Jon Fuller View Post
Mike's designs do seem to need shed loads of bow lift to get the best top end out of them. When TD and I raced the 26, I never stopped being amazed just how how much it needed / would take. If we set the trim to it's max speed position, whilst on the trailer, when you looked at the drive, it seemed inconceivable that it could be the most efficient angle, as the drive was virtually trimmed right out of the wear cheeks on the gimble. quite extraordinary.

Was never much fun, running close to 80 in calm conditions, trimmed like that, then finding one wave bigger than the rest. Could feel a little 'loose'.
The high rake helps exactly that problem, try and acheive a perfectly straight up and down outboard at max speed anything that looks as though the engine has passed that and you are most likely past the most efficient point of the propeller and are adding revs on the engine for no gain it's just throwing water in the air. You will find greater stability and a lot more control if you can keep the engine level. A level engine with 5 or 6 degrees on the boat seems to work well.
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Old 19-12-2009, 02:25 PM   #23
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Yes, I understand the principles.

We built a new 26, and incorporated a notched transom, in an effort to move the centre of lift forward, and increase the leverage for trim purposes. that worked for top speed, but the boat wasn't quite as good in the rough, plus, we then had a new Phantom 28 to beat. And that (Roger Severy's 'Wentworth Auto & Marine) was to be honest, in a different league when the waves came.
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Old 19-12-2009, 05:18 PM   #24
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Yes, I understand the principles.
Of Course, A trifle arrogant to think every post is directed at you though, what do you think this is YOUR forum
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Old 19-12-2009, 05:49 PM   #25
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Maybe a 24/26 raker, if you want loads of bow lift these props do it well, but out the box they are a handful but blueprinting then get the cupping done to your taste will be good.
I can only recommened these as i have used rakers for a few years now.
Good luck
Paul
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Old 19-12-2009, 06:00 PM   #26
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Quote:
Originally Posted by Techteam View Post
A trifle arrogant to think every post is directed at you though, what do you think this is YOUR forum
Well, you were quoting me! does that not mean it was a response to me?

Maybe if you hadn't quoted ME it would have looked like a general reply.

Mind you, you've quoted me with the arrogant comment too, but maybe you're not refering to me at all, and the 'quote' is another red herring (excuse the pun, I know we're talking Rakers, not Herrings)
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