Prop question

[Ky Grady]

I believe that the inline F200 and your F225 have different gear ratios. The F225 has a 2.0 ratio and the I4 is 1.86
If so, your prop selection may not be suitable for the I4

I know, that's why I keep referring him to speak with Ken. Just giving him my experience and info.

 

[seasick]

I believe that the inline F200 and your F225 have different gear ratios. The F225 has a 2.0 ratio and the I4 is 1.86
If so, your prop selection may not be suitable for the I4

I know, that's why I keep referring him to speak with Ken. Just giving him my experience and info.

Sorry if I\it seemed like I questioned your input.That wasn't my intention. I just wanted Ric to know that there may be several variables that need to be taken into account. I also agree that talking to a knowledgeable prop person is invaluable.

 

[Ky Grady]

I believe that the inline F200 and your F225 have different gear ratios. The F225 has a 2.0 ratio and the I4 is 1.86
If so, your prop selection may not be suitable for the I4

I know, that's why I keep referring him to speak with Ken. Just giving him my experience and info.

Sorry if I\it seemed like I questioned your input.That wasn't my intention. I just wanted Ric to know that there may be several variables that need to be taken into account. I also agree that talking to a knowledgeable prop person is invaluable.

Not at all. It's all good.

I also had said that I'm running a F225 and his needs might be different. :mrgreen:

I discussed with Ken what I had and what I was trying to achieve. He gave me two prop options and what both would do. I went with the OSF4 and have been extremely happy with it. The F225 lacks some grunt to push/lift my boat and with the 4 blade, it helps overcome it,,,,,,, until I hang the 250 on her!!! 8)

 

[ric2352]

Been talking with Ken online and read his tutorial on engine height....I have all the symptoms of engine too low for my hull.......will check that out first. Thanks for all the input. Professionally installed doesn't mean correct! I might have assumed too much...keep watching!

 

[Ky Grady]

Definitely keep us updated.

It might have been professionally installed in the standard location that works, but not necessarily ideal for maximum performance. Motor height and prop selection go hand in hand for best performance.

 

[ocnslr]

When they enter diameter, they use 70% of the measured distance from the hub center to the tip of the blade. It's not clear if that adjustment is taken into account in the Mercury Prop calculator app.

I don't believe you have that correct. Diameter is diameter - the size of the circle made by the rotating blades. Prop pitch is usually measured at .7 x radius, as the pitch actually changes along the radius of the prop. A blade that had the same pitch all along its radius would look like a ping pong paddle stuck into the hub, i.e. a flat blade.

 

[ric2352]

Ok....raised the engine to the third hole. Improved performance abit thru the range and 5600 rpm, 40 mph with trimmed up abit. Tried a 141/2x15 4 blade. Abit better to plane, mid range acceleration off the charts...it's a rocket! Important for my use. Top speed 42, 5700 rpm, engine trimmed up a bit. This was on flat water....fun to see how it works in a snotty ocean.