Who can figure this out?

[chrisk]

In 1994 Powerboat did a test on the 28 Cyclone with twin 465's / 1.36:1 gear ratio spinning a 25" 3mirage and the boat ran 85.2 mph at 5000 rpm's

In 1996 Powerboat did at test on the 28 Cyclone with tiwn 630HP's / 1.36:1 gear ratio spinning a 27" mirage and the boat ran 88.3 at 5200 rpm's

Thats a big horse power differnce for 3 mph... can any give any insight?

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