Cubes Equals Economy.
#1
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Cubes Equals Economy.
38 Foot deep vee.What differences will be seen going from 420hp 502's to 800hp 632's?
At the same speed will fuel useage be the same?
Forget the drives,maintenance etc.Just interested in your thoughts on fuel burn.
At the same speed will fuel useage be the same?
Forget the drives,maintenance etc.Just interested in your thoughts on fuel burn.
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More is More!
An 800 HP 632 engine is going to have a much greater BSFC (brake specific fuel consumption) than a 420HP 502, period!
The 800 hp engine is going to allow you to cruise at a faster speed or lower rpm than current 502 and that will save some fuel while running but the higher horspower potential of the 632 at speed will use a lot more fuel than the 502, but the speeds will be much greater. You see where I am going here?
Best Regards,
Ray @ Raylar
The 800 hp engine is going to allow you to cruise at a faster speed or lower rpm than current 502 and that will save some fuel while running but the higher horspower potential of the 632 at speed will use a lot more fuel than the 502, but the speeds will be much greater. You see where I am going here?
Best Regards,
Ray @ Raylar
#4
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An 800 HP 632 engine is going to have a much greater BSFC (brake specific fuel consumption) than a 420HP 502, period!
The 800 hp engine is going to allow you to cruise at a faster speed or lower rpm than current 502 and that will save some fuel while running but the higher horspower potential of the 632 at speed will use a lot more fuel than the 502, but the speeds will be much greater. You see where I am going here?
Best Regards,
Ray @ Raylar
The 800 hp engine is going to allow you to cruise at a faster speed or lower rpm than current 502 and that will save some fuel while running but the higher horspower potential of the 632 at speed will use a lot more fuel than the 502, but the speeds will be much greater. You see where I am going here?
Best Regards,
Ray @ Raylar
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I'm just trying to work out if i pull the small motors and fit the big.I already have both sets.
I use this boat around the islands and out to the reef.
If the both would use the same amount at the same speed i would be happy and do the swap.
#7
Geronimo36
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When I had the Scarab I'd burn 30 gallons per hour at cruise, which was 3700 rpms or 50 mph. Engines were 502", NA about 500-550 hp.
On the Apache (6 ft longer and a lot heavier), I burn 40 gallons per hour at 3700 rpms but now I'm running 61 mph at those R's. Plus, if I want to slow down to say 3200 rpms (50 mph) I will actually burn a little "less" fuel than the Scarab did at 3700. Engines are 580", blown, 830 hp.
So for 6 ft. in boat length, a couple thousand extra pounds, roughly 300 hp difference per engine and 10 mph gain in cruise, my fuel costs have largely remained the same.
However, get above 4200 rpms when the boost kicks in and all these figures quickly go out the window!!
#10
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A lot depends on how that hp is made.
an 800hp engine with an efficient blower like a whipple and a perfectly tuned EFI setup will get way better mpg than an 800hp with a big old fashioned roots blower and a couple Holley dominators.
Then again it will cost a lot more up front so comes down to when/where are you gonna spend the green.
an 800hp engine with an efficient blower like a whipple and a perfectly tuned EFI setup will get way better mpg than an 800hp with a big old fashioned roots blower and a couple Holley dominators.
Then again it will cost a lot more up front so comes down to when/where are you gonna spend the green.