Background - Got a 21' pontoon with 40 HP 2-stroke, wasn't expecting a
speed demon but was hoping I could squeeze a little more out of it.
Only hitting 13 and change (GPS measured speed).
Someone suggested that the prop was too big since it was only turning
5k rpms. So asked around, seemed like a 9 was the consensus. Check it
out yesterday, it has a 10 on it.

So I'm all excited thinking this is going to help me out... plug the
numbers in the prop calculator (
http://www.boatpropellers.com/propcalc.html ), maybe 1/2 mph increase?
Assuming the engine will spin up to 5500 with a 9. Sound right?

I wasn't sure about 'prop slip' so I reversed it out by what I knew
from current numbers. Came out to 45% and from what I read that's
possible with non-planing hulls. Guess I'm also wondering if there may
be more or less prop slip with the 9 vs. the 10.

What year and brand motor

wrote in message
ps.com...

Background - Got a 21' pontoon with 40 HP 2-stroke, wasn't expecting a
speed demon but was hoping I could squeeze a little more out of it.
Only hitting 13 and change (GPS measured speed).
Someone suggested that the prop was too big since it was only turning
5k rpms. So asked around, seemed like a 9 was the consensus. Check it
out yesterday, it has a 10 on it.

So I'm all excited thinking this is going to help me out... plug the
numbers in the prop calculator (
http://www.boatpropellers.com/propcalc.html ), maybe 1/2 mph increase?
Assuming the engine will spin up to 5500 with a 9. Sound right?

I wasn't sure about 'prop slip' so I reversed it out by what I knew
from current numbers. Came out to 45% and from what I read that's
possible with non-planing hulls. Guess I'm also wondering if there may
be more or less prop slip with the 9 vs. the 10.

wrote in message
ps.com...

Background - Got a 21' pontoon with 40 HP 2-stroke, wasn't expecting a
speed demon but was hoping I could squeeze a little more out of it.
Only hitting 13 and change (GPS measured speed).
Someone suggested that the prop was too big since it was only turning
5k rpms. So asked around, seemed like a 9 was the consensus. Check it
out yesterday, it has a 10 on it.

So I'm all excited thinking this is going to help me out... plug the
numbers in the prop calculator (
http://www.boatpropellers.com/propcalc.html ), maybe 1/2 mph increase?
Assuming the engine will spin up to 5500 with a 9. Sound right?

I wasn't sure about 'prop slip' so I reversed it out by what I knew
from current numbers. Came out to 45% and from what I read that's
possible with non-planing hulls. Guess I'm also wondering if there may
be more or less prop slip with the 9 vs. the 10.


Ron Knapik wrote:
What year and brand motor


1998 Mercury

OK, if it was a Johnson, they make a hydrus prop specifically for pontoon
application. I'm sure merc makes something on the same line, check with a
Merc dealer.

Ron

wrote in message
oups.com...
wrote in message
ps.com...

Background - Got a 21' pontoon with 40 HP 2-stroke, wasn't expecting a
speed demon but was hoping I could squeeze a little more out of it.
Only hitting 13 and change (GPS measured speed).
Someone suggested that the prop was too big since it was only turning
5k rpms. So asked around, seemed like a 9 was the consensus. Check
it
out yesterday, it has a 10 on it.

So I'm all excited thinking this is going to help me out... plug the
numbers in the prop calculator (
http://www.boatpropellers.com/propcalc.html ), maybe 1/2 mph increase?
Assuming the engine will spin up to 5500 with a 9. Sound right?

I wasn't sure about 'prop slip' so I reversed it out by what I knew
from current numbers. Came out to 45% and from what I read that's
possible with non-planing hulls. Guess I'm also wondering if there
may
be more or less prop slip with the 9 vs. the 10.


Ron Knapik wrote:
What year and brand motor


1998 Mercury

Mercury makes a bigfoot prop for pontoons
"Ron Knapik" wrote in message
...
OK, if it was a Johnson, they make a hydrus prop specifically for pontoon
application. I'm sure merc makes something on the same line, check with a
Merc dealer.

Ron

wrote in message
oups.com...
wrote in message
ps.com...

Background - Got a 21' pontoon with 40 HP 2-stroke, wasn't expecting
a
speed demon but was hoping I could squeeze a little more out of it.
Only hitting 13 and change (GPS measured speed).
Someone suggested that the prop was too big since it was only turning
5k rpms. So asked around, seemed like a 9 was the consensus. Check
it
out yesterday, it has a 10 on it.

So I'm all excited thinking this is going to help me out... plug the
numbers in the prop calculator (
http://www.boatpropellers.com/propcalc.html ), maybe 1/2 mph
increase?
Assuming the engine will spin up to 5500 with a 9. Sound right?

I wasn't sure about 'prop slip' so I reversed it out by what I knew
from current numbers. Came out to 45% and from what I read that's
possible with non-planing hulls. Guess I'm also wondering if there
may
be more or less prop slip with the 9 vs. the 10.


Ron Knapik wrote:
What year and brand motor


1998 Mercury

FREDO wrote:
Mercury makes a bigfoot prop for pontoons
"Ron Knapik" wrote in message
...

OK, if it was a Johnson, they make a hydrus prop specifically for pontoon
application. I'm sure merc makes something on the same line, check with a
Merc dealer.

Ron

The Mercury Bigfoot is more then just a prop..

From the Mercury site:
"BigFoot models feature greater torque, larger propellers, and beefed up
drive-train components to handle the extra weight and turbulence of
pontoons."

Capt Jack R..


wrote in message
groups.com...

wrote in message
groups.com...

Background - Got a 21' pontoon with 40 HP 2-stroke, wasn't expecting
a
speed demon but was hoping I could squeeze a little more out of it.
Only hitting 13 and change (GPS measured speed).
Someone suggested that the prop was too big since it was only turning
5k rpms. So asked around, seemed like a 9 was the consensus. Check

it

out yesterday, it has a 10 on it.

So I'm all excited thinking this is going to help me out... plug the
numbers in the prop calculator (
http://www.boatpropellers.com/propcalc.html ), maybe 1/2 mph
increase?
Assuming the engine will spin up to 5500 with a 9. Sound right?

I wasn't sure about 'prop slip' so I reversed it out by what I knew
from current numbers. Came out to 45% and from what I read that's
possible with non-planing hulls. Guess I'm also wondering if there

may

be more or less prop slip with the 9 vs. the 10.


Ron Knapik wrote:

What year and brand motor


1998 Mercury

wrote:
Background - Got a 21' pontoon with 40 HP 2-stroke, wasn't expecting a
speed demon but was hoping I could squeeze a little more out of it.
Only hitting 13 and change (GPS measured speed).
Someone suggested that the prop was too big since it was only turning
5k rpms. So asked around, seemed like a 9 was the consensus. Check it
out yesterday, it has a 10 on it.

So I'm all excited thinking this is going to help me out... plug the
numbers in the prop calculator (
http://www.boatpropellers.com/propcalc.html ), maybe 1/2 mph increase?
Assuming the engine will spin up to 5500 with a 9. Sound right?

I wasn't sure about 'prop slip' so I reversed it out by what I knew
from current numbers. Came out to 45% and from what I read that's
possible with non-planing hulls. Guess I'm also wondering if there may
be more or less prop slip with the 9 vs. the 10.


Don't know about the prop slip stuff. But my 20ft pontoon with a 60hp
four stroke bigfoot would hit 18mph with me and one other person on it
when it was new (GPS).

Now with the family (two kids and da wife with a little growth on the
logs it will run about 15 mph. (Speedo) the gps was not hooked up the
last few time I was out on it.

Capt Jack R..