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Old 01 December 2005, 13:36   #21
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the two outside engines appear to be mounted higher on the transom than the inboard ones - is there a reason?
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Old 01 December 2005, 13:40   #22
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Originally Posted by Petrov
Nops, there is no cavitation at all and the middle engines has UL rigg and the side engines are Xl.
We didnt have the right props on (25 on the sides and 23 in the middle, we had a topspeed of 59 knots and an acceleration of 0-50 knots in seconds.
Boat is 13m and 3,2m wide and has a weight of arond 3,5 tons (dont have the exact weight)
Does that weight include fuel, our 9m is 3 tonne dry. When first launched we had 52knots with 1300 litres of fuel onboard
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Old 01 December 2005, 13:51   #23
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Originally Posted by Mollulnan
Correct me if I'm wrong, but I can't see that four large outboards mounted so closely together can be anything like efficient.
ok then, your wrong!
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Old 01 December 2005, 13:58   #24
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Originally Posted by Dirk Diggler
ok then, your wrong!
WHY???

I can't see how 4 props that close together aren't going to interfere with each other.

I can understand the logic of the outer ones being higher to follow the shape of the V.
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Old 01 December 2005, 14:11   #25
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WHY???

I can't see how 4 props that close together aren't going to interfere with each other.
Answer your own question. Why would they?
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Old 01 December 2005, 14:21   #26
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Originally Posted by jwalker
Answer your own question. Why would they?

Look out Codders! Here comes Johnny Ramjet! Prepare to be bored rigid!!
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Old 01 December 2005, 14:22   #27
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I take it you have just bought this beast then
No its not my beast, we went for a 10,5m with 3 Suz.

Quote:
Does that weight include fuel, our 9m is 3 tonne dry. When first launched we had 52knots with 1300 litres of fuel onboard
Without fuel but if you fill 1500 liters of fuel you will maybe loose one knot when you have 4 engines so it doesnt effect the speed very much.

Quote:
I can't see how 4 props that close together aren't going to interfere with each other.
Its a lot of trim before you get them perfect but the 2 middle engines are like a usual twin setup with UL rigg, and when you use the shorter rigg on the side they pic up water higher up to the surface wich means no interfear from the lower engines, the UL shafts are very deep down are always very wet, you have a lot of power wich means that you dont have to steer much before the boat goes were you want.
If you install a twin (or more) setup perfect and very close to each other you will have more performance than if the engines are far away from each other.
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Old 02 December 2005, 10:36   #28
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Originally Posted by jwalker
Answer your own question. Why would they?
Let's see codder's google his way out of this!
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Old 02 December 2005, 11:09   #29
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Originally Posted by Petrov
Ring powercraft

Here it is with 4 yammies, i filmed it yesterday.

Acceleration
That looks really un-stable on the video - maybe pulling away quickly but it's all over the place!

Did the handling settle down?
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Old 02 December 2005, 12:22   #30
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Originally Posted by Dirk Diggler
Let's see codder's google his way out of this!
Why would I need to - if it isn't blatantly obvious then I give up!!!!
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