94 Mph

That must be nearly 1 mph per hp,

Does a bigger swell make you go faster cause going down a big wave is like going down hill?

So, maybe my estimate of 110 was a little on the low side!!!

I reckon in a 20 foot swell with my 260 hp...................... :dizzy:
 
What you mean it won't do this speed:cry:
I've just part exchanged my 300 drag for this rig.

:drain: :drain: :drain:

Cyco
 

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of course it is! any boat on a trailer is as fast as the vehicle towing it!!!!!!
the OCR boys do around 60mph with 1.8 ltr 130hp engines.
so maybe in a large swell, downhill................................;p;
 
Well I'm not so sure, a 135hp ford v6/jet in didy speedboat might top 50, and back in 88 a 1.8 OCR B boat ran almost 69mph (Jeff Locock, on Windermere) probably with an old straight six Merc! so it's not completly out of the question.
 
94 mph possible but unlikely.

Theoretical top speeds can be easily calculated. Just take max revs X(times) propeller pitch/(divided by) gear ratio X .0094976. Multiply by the inverse of prop slippage (typically 75 -85% for a performance type monohull) and there you have it in mph.

Quick note to Essex Navee from a not quite 'Boy Racer' type - 60 kn is actually 69 mph since 1 knot = 1.15 mph.
 
Ned said:
Theoretical top speeds can be easily calculated. Just take max revs X(times) propeller pitch/(divided by) gear ratio X .0094976. Multiply by the inverse of prop slippage (typically 75 -85% for a performance type monohull) and there you have it in mph.

So let me get this right, if I put 40" pitch props on my boat, it'll do 100mph!...****, If I'd known it was as simple as just adding pitch I'd have done it years ago!:brown:
 

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