Actual Outboard HP Vs Claimed?? Find the truth?

[black runner]

HP rating is a poor indicator of an outboards potential performance. HP is simply a measurement of work done over a period of time. A manufacturer can boost hp simply by increasing the max WOT spec without changing aything else - for a given motor the HP increases simply because it is doing more RPM, but at cruise changes are minimal. Thats why the similar cc DF 115 and 140 have not much difference in torque at 4500 however the 140 max HP is at 6000 compared to the 115 at 5500.

And so it goes on through the list with torque figures showing much smaller variations than MAX HP figures at WOT - a place where not many of us would want to be operating except racing/bass comps maybe.

For a given HP and technology I like to look at CC, and motor weight

Cheers

[Moonlighter]

Thanks Honda - excellent source of information there - exactly what I had hoped we could find.

I agree that hp is not the be-all-and-end-all when it comes to performance. Obviously torque is important, as are gearbox ratios. What would be really great is for each motor to see a graph with hp, torque and fuel use overlayed together, and all done to the same standard. Then we'd be cookin!

But at least when you've got some accurate data on hp, you've got to be one step ahead of having nothing!

Thanks again, Honda! Excellent work! (PS Honda - my new boat is back from the paint shop and fitout should be completed within 10 days, then it's into the container, onto a ship, and on its way to Aus across the Tasman. Will talk to you re hooking Suzi 115 up to Lowrance HDS then. Can't wait! )

Cheers

ML

[honda900]

No probs ML..

it will be a long 10 days...

Regards
HOnda

[suzygs1000]

HP rating is a poor indicator of an outboards potential performance. HP is simply a measurement of work done over a period of time. A manufacturer can boost hp simply by increasing the max WOT spec without changing aything else - for a given motor the HP increases simply because it is doing more RPM, but at cruise changes are minimal. Thats why the similar cc DF 115 and 140 have not much difference in torque at 4500 however the 140 max HP is at 6000 compared to the 115 at 5500.

And so it goes on through the list with torque figures showing much smaller variations than MAX HP figures at WOT - a place where not many of us would want to be operating except racing/bass comps maybe.

For a given HP and technology I like to look at CC, and motor weight

Cheers

And yet the 140 runs a much bigger prop??

Dave.

[black runner]

Hi Dave,

Not sure what you mean, the 115/140 prop specs are identical. For a given hull the 140 would be able to spin a bigger prop than the 115 but only marginally bigger compared to the 150. The great thing about the 140 is that it fills the weight/hp void between 115 and 150 lacking in other 4 stroke brands.

Cheers