Repowering 2007 330 Express 350s or 425's

Mangrum27

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I am curious if anyone has repowered with Suzuki's 350's or if even GW would allow 425's? Anyone ever tried to ask for a higher power rating on a boat?
 

seasick

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I am curious if anyone has repowered with Suzuki's 350's or if even GW would allow 425's? Anyone ever tried to ask for a higher power rating on a boat?
If you mean, will Grady rate your boat for more horse power and document that, the answer is no.
The rating is one part of the ABYC certification process, a complicated and expensive task.
 
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Stephnic

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I have a friend that repowered his 2004 with twin Yamaha 300 with 4 blade props the boat runs great.
 

Stephnic

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Not sure cruising speed just put the boat back in the water I can tell you it was doing 40.7 mph at 5700 rpm’s
 

moklodge

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Boat was beefed up for the F350s in 2008 and again in 2020 for the 425s. A 2007 should not be powered with more than F300s.
 

Mangrum27

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To my knowledge it was 04 when beefed up and power rating is 700. I may be wrong but that is what i have read.
 

Lucky13

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To my knowledge it was 04 when beefed up and power rating is 700. I may be wrong but that is what i have read.
max HP in 07 is 600HP. I repowered my 07 with 300's and what a difference it makes.
 

Mangrum27

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I respectfully disagree as the owners manual clearly states 700hp is max. However what is cruise and top speed with 300s?
 

Fishtales

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I wouldn't exceed the manufacturers spec for HP. Could run into issues in the event of a hull failure or insurance claim.