Any 42' get 1 nmpg?

f2c

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Any downeast boats in the 42' size get this mpg #'s?
 

f2c

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1NMPG at cruise...

I of course mean at cruise. I got #'s on a 42 H&H and it is burning 28 gph cruising at 18 kts. T. Am I being unrealistic?hat's not as efficient as I'm hoping for
 

Helen L

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I get about 1.9nmpg at cruising and I'm 47'. Trick is to have a boat that's slow as hell.
 

Blitzen

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My buddys 42 Duffy, powered with a 800 Cat and weighs in at about 35,000lbs burns 28-29 gal/hr at 19kts, full fuel 700+gallons, 1000lbs ice, bait and crew. This is a flybridge boat with 2:1 reduction and 5 bladed prop.
 

Powderpro

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Any downeast boats in the 42' size get this mpg #'s?
If you had a very efficient hull, a big prop, no bridge, and a light weight basic 42', you may be able get fairly close to 1 nmpg at a 16- 18 knot cruise, but I think everything would have to be working in your favor to even get close. Sounds like the #'s you quoted for the 42' H&H are probably typical and what you could expect for most 42' boats.

This is just my opinion, and I could be wrong. But an efficient 42' boat would be a 40' Young brothers lengthened 2' by Stewart Workman; install a 500hp Deere, Volvo, Cat 9 liter with a 2.5 reduction, spinning a 32" diameter prop, build it light weight, no bridge, no extra comforts, and I bet you could hit 1 nmpg at 16-18 knots. 'Course, I could be wrong, but the 40' Young Brothers is more slim at 13'6" than the other 40's and would likely push a little easier than the wider boats.
 
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f2c

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Wow. That is pretty much exactly what I was hoping to see, although with a light preference for a higher cruise speed.

No other hull changes? Those big differences were due soley to shifting the main 24" aft of normal? Did it then need an engine box exteded back from the floor of the wheelhouse?
 

Powderpro

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430 american, 450 metric. Same engine
I must say, those are impressive performance numbers for a 430hp engine in a large 42' boat. Must be a light boat and a good running engine. I was comparing the torque curves of the Diamond 430hp vs. the new QSC 500hp, and the QSC has a much more robust torque curve, peaks at 1,327 ft/lbs. The 430hp Diamond peaks at 1,029 ft/lbs. As I said before, keep the boat light and simple, install a lighter weight 500hp engine like a 9 liter or QSC, 2.5 reduction, big prop, and that will be the most efficient combo possible in a 42' boat imo. And with a 500hp engine, you should be able to beat Sockeye's numbers in speed.
 

Whatta Catch

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Splashed the Boat today and ran her to check everything out. It's a 40 H&H with a 650 Mack. At 14-15 knots we were burning 15 -16 GPH with the tide. At 19 Knots it was 26 GPH against the tide as per the Flow Scan.
 

WoundUpMarine

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