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Clams Canino
 
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Default Selecting HP for given hull (outboard)

"del cecchi" wrote in message news:NTKfb.139

The bigger motor won't burn less gas at the same speed fer sure.
Maybe not much more, but not less.



Bzzzzzzt.

Anyone who reads this NG can tell you that I had FOUR different motors on
the back of my (dearly departed) Four Winns last year.

76ci 80hp - 89ci 100hp - 99ci 115hp - 99ci130hp (crankshaft ratings to keep
this simple)
All tested with a 14, 15, and 17 pitch stainless props.

I can tell you *unequivicably* that in the case of 2-stoke outboards, output
is governed by two factors - spark advance and throttle openings.

If you have to run a 100hp with spark at max advance and the throttle body
3/4 open to achieve a speed of 25 mph but you can take a 130 and do the same
thing at max advance with the throttle body just cracked a bit - guess which
motor will deliver better mileage??

And that's not even accounting for the propping up you can do with more HP.

I'm sorry, but that sentance could not be *more* wrong.

If I ever wanna help this world deplete it's gas supply - I'll start by
putting the 80hp (I kept it) on the PM-II and pulling tubers all day - OK?


-W