Prop Pitch???

[Muskieman]

Here goes..

 

On my 1998, 30hp Evinrude Tiller Short Shaft... Mounted on a 2002 Tracker SGV14T

 

I have a 11* 10 1/4" prop that pushes me to 31.5 mph on GPS single and 27.6 with a buddy..

I have no problems getting to plane single or double.

 

I was in need of a new one and a buddy gave me his.. It fits like a glove it's off of a 1998 25hp Johnny.

It is a 13* 10" ... how will this affect my performance???

 

Slower to plane and a faster top end or faster to plane and a slower top end?

 

An inquiring mind needs to know..

 

THANKS A MILLION!!!

 

RFS

[wallyboss]

I am pretty sure that it will be slower to plane but more top end. But before you change the pitch on your motor the rpm's have to be checked out.

According to the max rpm of your motor then you will know if it's going to work out for you.

 

WOT and proper trim check your RPM's then lets say your max rpm on the motor is 5500 and you are hitting 5900 then the new prop would be perfect. cause for every 1 inch of pitch more you will drop the rpm by 200. but if you are already at say 5300 and you raise the picth by 2" then your rpm will drop to 4900. so it wouldn't be a change that you would want to do. What you want is tha at WOT properly trimmed that yoiur engine is running at it's max rpms.

[Jonny Rebel]

Will probably be close to the same.

[BillM]

A question for the pros:

 

Our 40HP 4stroke Honda tiller seems like it doesn't pick up much speed at all with the last 1/4 throttle at all. It rips out of the bottom end and gets up on plane in no time. Would changing to a prop with a different pitch help? Currently on GPS I am hitting around 45km/h with myself in the boat.

[Fisherman]

I believe I have the same thing as you, just a smaller(25) engine. That last 1/4 of throtttle doesn't quite translate into 1/4 more speed, I think it's just the length of the throttle cable and how it's positioned on the linkage. If you check it with the engine off, in gear, and slow rotate the handle on a tiller or remote on a s/c, you'll see what I mean.

[BillM]

I believe I have the same thing as you, just a smaller(25) engine. That last 1/4 of throtttle doesn't quite translate into 1/4 more speed, I think it's just the length of the throttle cable and how it's positioned on the linkage. If you check it with the engine off, in gear, and slow rotate the handle on a tiller or remote on a s/c, you'll see what I mean.

 

I hear an increase in RPM with the last 1/4 throttle, but I don't gain any speed. That's why I'm thinking the prop could use a bump or decrease in pitch (which ever one gives me some more top end)

[Woodsman]

Here goes..

 

On my 1998, 30hp Evinrude Tiller Short Shaft... Mounted on a 2002 Tracker SGV14T

 

I have a 11* 10 1/4" prop that pushes me to 31.5 mph on GPS single and 27.6 with a buddy..

I have no problems getting to plane single or double.

Seems about right for that set up.

I was in need of a new one and a buddy gave me his.. It fits like a glove it's off of a 1998 25hp Johnny.

It is a 13* 10" ... how will this affect my performance???

Slower to plane and a faster top end or faster to plane and a slower top end?

Yes slower to plane & possibly less top end.

With the prop installed check your WOT rpm. I suspect it will be well below the recommended range. Check it with the boat loaded the way you typically use it. If it is below the recommended range loaded the way you typically use it you have too much prop. Either reduce the diameter or pitch(or both) to bring the WOT back within the recommended range.

 

Rick

[Muskieman]

Prop update....

 

Less Bottom End torque..a little slower to plane..I'd have a hard time pulling up a skier

 

MUCH more middle range ...

 

and just under 2 MPH faster on top speed..

[corvette1]

on my lund pro-v i have a 115 2 stroke with a 19 pitch ss it gets more top end when i put my 17 pitch ss i lose 3 mph but jumps right on plane hope this helps