Does 500HP=?
08-29-2007, 06:56 PM
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Does 500HP=?
Is the 500HP (1998 carbed) engine rated at 500 horsepower? I've been told it's rated at 470? Please help me get this cleared up. I even called the dealers in town and they didn't seem to know.
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08-31-2007, 06:07 PM
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08-31-2007, 07:36 PM
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09-01-2007, 05:18 AM
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The confusion isnīt helped by the fact that Marc racing rates 525 and everything thereafter with PROPSHAFT horsepower - but are very hesitent to quote a crankshaft figure. The 525 propshaft hp motor produces around 560 crankshaft hp (independantly tested).
The 496 motor, like the 500, is CRANKSHAFT rated - at 425 hp, as independant tests have shown.
Crankshaft hp
496HO - 425 hp
HP500 - 500 hp
525EFi - 560 hp
Another twist in the story is that in 2000, when Merc racing was offering both the HP500 (carb) and the 500EFi motors for the APBA Factory 1 race series, they loaded the EFi boats with a 250 pound weight penalty to keep things fair (Powerboat Magazine Sept 2000).
The 496 motor, like the 500, is CRANKSHAFT rated - at 425 hp, as independant tests have shown.
Crankshaft hp
496HO - 425 hp
HP500 - 500 hp
525EFi - 560 hp
Another twist in the story is that in 2000, when Merc racing was offering both the HP500 (carb) and the 500EFi motors for the APBA Factory 1 race series, they loaded the EFi boats with a 250 pound weight penalty to keep things fair (Powerboat Magazine Sept 2000).
