single VS Twin fuel economy
#1
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OK, big question here :
Same boat, let's say same horse-power or near....
Difference in fuel economy :
Exemple:
29 f. with two 7.4 MPI's
29 f. with a single 525 SC
Wich config is the winner in fuel economy and is there a huge difference?
Same boat, let's say same horse-power or near....
Difference in fuel economy :
Exemple:
29 f. with two 7.4 MPI's
29 f. with a single 525 SC
Wich config is the winner in fuel economy and is there a huge difference?
#3
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Dont forget to add the cost of a bravo upper, coupler, and gimbal ring with the bigger power. They'll wear out on the 7.4s, just not as fast.
Also consider that 7.4s last almost forever. I've seen carb 330 motors that still ran well after 1500 hrs. My 525SCs needed freshening after about 800 hrs.
I never really cared about fuel costs.
Gary
Also consider that 7.4s last almost forever. I've seen carb 330 motors that still ran well after 1500 hrs. My 525SCs needed freshening after about 800 hrs.
I never really cared about fuel costs.
Gary
#4
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A few years back, me and a buddy of
mine ran from Duluth to Two Harbors
and back on lake Superior.
My boat had twin 7.4's, his had a
single 502 mpi, both were 29 ft.
boats.
I used 100 gallons of fuel,
he used 80 gallons.
I was running 3000 rpm most
of the way, he was running
4000 rpm most of the way.
If my memory serves me correctly,
(from reviewing various boat tests)
I think I remember seeing that a
7.4 consumes around 30 g.p.h.
at w.o.t.
While a 525 consumes around 50 g.p.h.
at w.o.t.
So, I would say there's not that great
of a difference.
jt
mine ran from Duluth to Two Harbors
and back on lake Superior.
My boat had twin 7.4's, his had a
single 502 mpi, both were 29 ft.
boats.
I used 100 gallons of fuel,
he used 80 gallons.
I was running 3000 rpm most
of the way, he was running
4000 rpm most of the way.
If my memory serves me correctly,
(from reviewing various boat tests)
I think I remember seeing that a
7.4 consumes around 30 g.p.h.
at w.o.t.
While a 525 consumes around 50 g.p.h.
at w.o.t.
So, I would say there's not that great
of a difference.
jt
#6
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There is no winner in fuel economy in boats, they all like the gas. But hey we buy boats not to worry about gas economy. When comparing the two you should be thinking about dock manuverability, handling, maintainence, extra weight of two, do you want extra storage in engine compartment and other stuff.
#7
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Zanie.... : Petit coquin.... very funny... :-)
Well, considering I am NOT a millionaire...
Some like me will spend time on getting all they can with less $$$
Others will spend thousands of $ for one MPH. Well, unfortunatly, I am in the first category. ;-) Happy for those in the second category...
Till I join the second category, I have something called : A BUDGET ;-)
That gives me a new tread Idea : WHO IS RICH HERE? ;-) ;-)
Well, considering I am NOT a millionaire...
Some like me will spend time on getting all they can with less $$$
Others will spend thousands of $ for one MPH. Well, unfortunatly, I am in the first category. ;-) Happy for those in the second category...
Till I join the second category, I have something called : A BUDGET ;-)
That gives me a new tread Idea : WHO IS RICH HERE? ;-) ;-)
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08-25-2003 08:28 AM