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Steve September 8th 04 11:23 PM

prop help?
 
I'm looking for help in selecting a new prop. I'm currently running a 14
1/4x 23p
3 blade that came on the boat from the factory. The boat is a 2003 Larson
SEI 190 (open bow runabout) with a 4.3 volvo sx sterndrive. It will turn
this prop 4600 rpms (4200-4600 reccomended by volvo at WOT) and 49 mph
according to speedometer at WOT.

This summer we have started doing alot of slalom skiing. Needless to say it
is a bit lacking on power to pull up a 200# plus skier . I have been looking
at 4 and 5 blade props but am at a loss as to what size should work best for
me. Also is there a big trade off for power to loss of top end? I need
something that will be a good all around prop as we do alot of tubing and
wakeboarding as well as just cruising around the lake.

I do not have a local dealer that will let me try out different sizes. I'm
not afraid to spend some $ on a good prop, but dont want to experiment with
sizes at the prices of these props.

Thanks for any help Steve




Woodchuck September 8th 04 11:55 PM

You can't have your cake and eat it too! That said since you need the low
end pull for all the fun then drop pitch to 21 but keep an eye on your RPM
for them speed runs. You should have no worries running that 4.3 to 4800. I
had a 5.7 which was in the same 4200-4600 but propped for 4900rpm, 10 years
later and still no engine problems.


"Steve" wrote in message
...
I'm looking for help in selecting a new prop. I'm currently running a 14
1/4x 23p
3 blade that came on the boat from the factory. The boat is a 2003 Larson
SEI 190 (open bow runabout) with a 4.3 volvo sx sterndrive. It will turn
this prop 4600 rpms (4200-4600 reccomended by volvo at WOT) and 49 mph
according to speedometer at WOT.

This summer we have started doing alot of slalom skiing. Needless to say

it
is a bit lacking on power to pull up a 200# plus skier . I have been

looking
at 4 and 5 blade props but am at a loss as to what size should work best

for
me. Also is there a big trade off for power to loss of top end? I need
something that will be a good all around prop as we do alot of tubing and
wakeboarding as well as just cruising around the lake.

I do not have a local dealer that will let me try out different sizes. I'm
not afraid to spend some $ on a good prop, but dont want to experiment

with
sizes at the prices of these props.

Thanks for any help Steve






Tony Thomas September 9th 04 12:24 AM

Go w/ the 4 blade SS performance prop in a 22 or 23 pitch. Diameter will be
a little less which will make up for the extra blade surface. Expect to
loose about 3 mph on top end. Reason I say 22 or 23 is the 23 will be the
right prop but some manufacturers make 22, 24 and some make 21, 23. The 22
will loose about 5 mph on top end over your current configuration.

You might also install a whale tail. They do help for skiing purposes.

--
Tony
my boats at http://t.thomas.home.mchsi.com

"Steve" wrote in message
...
I'm looking for help in selecting a new prop. I'm currently running a 14
1/4x 23p
3 blade that came on the boat from the factory. The boat is a 2003 Larson
SEI 190 (open bow runabout) with a 4.3 volvo sx sterndrive. It will turn
this prop 4600 rpms (4200-4600 reccomended by volvo at WOT) and 49 mph
according to speedometer at WOT.

This summer we have started doing alot of slalom skiing. Needless to say

it
is a bit lacking on power to pull up a 200# plus skier . I have been

looking
at 4 and 5 blade props but am at a loss as to what size should work best

for
me. Also is there a big trade off for power to loss of top end? I need
something that will be a good all around prop as we do alot of tubing and
wakeboarding as well as just cruising around the lake.

I do not have a local dealer that will let me try out different sizes. I'm
not afraid to spend some $ on a good prop, but dont want to experiment

with
sizes at the prices of these props.

Thanks for any help Steve






trainfan1 September 9th 04 01:10 AM

Steve wrote:
I'm looking for help in selecting a new prop. I'm currently running a 14
1/4x 23p
3 blade that came on the boat from the factory. The boat is a 2003 Larson
SEI 190 (open bow runabout) with a 4.3 volvo sx sterndrive. It will turn
this prop 4600 rpms (4200-4600 reccomended by volvo at WOT) and 49 mph
according to speedometer at WOT.

This summer we have started doing alot of slalom skiing. Needless to say it
is a bit lacking on power to pull up a 200# plus skier . I have been looking
at 4 and 5 blade props but am at a loss as to what size should work best for
me. Also is there a big trade off for power to loss of top end? I need
something that will be a good all around prop as we do alot of tubing and
wakeboarding as well as just cruising around the lake.

I do not have a local dealer that will let me try out different sizes. I'm
not afraid to spend some $ on a good prop, but dont want to experiment with
sizes at the prices of these props.

Thanks for any help Steve




I would go for a 3 blade stainless 21" double cupped. It should give
you improved holeshot with superior water-holding & comparable top end
speed & rpm's... maybe just a little higher rpm's. For a wild set-up,
go for the Land & Sea Torque-Shift variable pitch prop... holeshot out
at 13"-14" and top end speed at 23"-24". Your boat will "jump" out of
the water!

Rob

Tony Thomas September 9th 04 02:00 AM

Not sure why you say this Rob. A 21 double cupped will definetly help on
the hole shot but will overrev by about 250 rpms. The double cupping adds
bite and creates extra drag which reduces the rpms without adding pitch. It
will also slow the boat down considerable due to the fact that your now
turning a 21 instead of a 23. Expect about 5 mph drop in top end if you
keep the rpms at 4600 (don't overrev).

As for the Torque Shift prop - I don't care for the maintenance of the prop
springs and the cracked hubs and the stress on the lower unit. They do work
but are not worth the money and maintenance costs.

--
Tony
my boats at http://t.thomas.home.mchsi.com

"trainfan1" wrote in message
...
Steve wrote:
I'm looking for help in selecting a new prop. I'm currently running a 14
1/4x 23p
3 blade that came on the boat from the factory. The boat is a 2003

Larson
SEI 190 (open bow runabout) with a 4.3 volvo sx sterndrive. It will turn
this prop 4600 rpms (4200-4600 reccomended by volvo at WOT) and 49 mph
according to speedometer at WOT.

This summer we have started doing alot of slalom skiing. Needless to say

it
is a bit lacking on power to pull up a 200# plus skier . I have been

looking
at 4 and 5 blade props but am at a loss as to what size should work best

for
me. Also is there a big trade off for power to loss of top end? I need
something that will be a good all around prop as we do alot of tubing

and
wakeboarding as well as just cruising around the lake.

I do not have a local dealer that will let me try out different sizes.

I'm
not afraid to spend some $ on a good prop, but dont want to experiment

with
sizes at the prices of these props.

Thanks for any help Steve




I would go for a 3 blade stainless 21" double cupped. It should give
you improved holeshot with superior water-holding & comparable top end
speed & rpm's... maybe just a little higher rpm's. For a wild set-up,
go for the Land & Sea Torque-Shift variable pitch prop... holeshot out
at 13"-14" and top end speed at 23"-24". Your boat will "jump" out of
the water!

Rob




Steve September 9th 04 04:34 AM

Do any of you have any experience with the Mercury High Five props?


Steve wrote in message
...
I'm looking for help in selecting a new prop. I'm currently running a 14
1/4x 23p
3 blade that came on the boat from the factory. The boat is a 2003 Larson
SEI 190 (open bow runabout) with a 4.3 volvo sx sterndrive. It will turn
this prop 4600 rpms (4200-4600 reccomended by volvo at WOT) and 49 mph
according to speedometer at WOT.

This summer we have started doing alot of slalom skiing. Needless to say

it
is a bit lacking on power to pull up a 200# plus skier . I have been

looking
at 4 and 5 blade props but am at a loss as to what size should work best

for
me. Also is there a big trade off for power to loss of top end? I need
something that will be a good all around prop as we do alot of tubing and
wakeboarding as well as just cruising around the lake.

I do not have a local dealer that will let me try out different sizes. I'm
not afraid to spend some $ on a good prop, but dont want to experiment

with
sizes at the prices of these props.

Thanks for any help Steve






Short Wave Sportfishing September 9th 04 11:40 AM

On Thu, 09 Sep 2004 01:00:54 GMT, "Tony Thomas"
wrote:

Not sure why you say this Rob. A 21 double cupped will definetly help on
the hole shot but will overrev by about 250 rpms. The double cupping adds
bite and creates extra drag which reduces the rpms without adding pitch. It
will also slow the boat down considerable due to the fact that your now
turning a 21 instead of a 23. Expect about 5 mph drop in top end if you
keep the rpms at 4600 (don't overrev).

As for the Torque Shift prop - I don't care for the maintenance of the prop
springs and the cracked hubs and the stress on the lower unit. They do work
but are not worth the money and maintenance costs.


I have a question for you.

My friend who has the engine problems also has a prop problem. He is
currently swinging a 14 1/2 x 23 on an Evinrude 200 FICHTand gets
about 38 mph at 5400 rpm WOT fully trimmed out. He can change pitch
which changes RPM but no relative increase in speed - in fact with a
21, he got 5700 RPM and lost four mph. The engine is properly
installed, etc.

Any idea why?

Later,

Tom

trainfan1 September 9th 04 12:10 PM

Tony Thomas wrote:
Not sure why you say this Rob. A 21 double cupped will definetly help on
the hole shot but will overrev by about 250 rpms. The double cupping adds
bite and creates extra drag which reduces the rpms without adding pitch.


You almost answer your own question here...

It
will also slow the boat down considerable due to the fact that your now
turning a 21 instead of a 23. Expect about 5 mph drop in top end if you
keep the rpms at 4600 (don't overrev).


This should be somewhat offset by the switch to a precision SS prop from
a cast aluminum wheel - typically minimal loss of top end...

As for the Torque Shift prop - I don't care for the maintenance of the prop
springs and the cracked hubs and the stress on the lower unit. They do work
but are not worth the money and maintenance costs.


For a Mercruiser Alpha, you are correct, but a Volvo SX should be able
to handle it... esp. with the V-6.

Rob

Tony Thomas September 10th 04 03:48 AM

The high five is a very good prop but most people don't want to spend the
money for one. Should work great.

--
Tony
my boats at http://t.thomas.home.mchsi.com

"Steve" wrote in message
...
Do any of you have any experience with the Mercury High Five props?


Steve wrote in message
...
I'm looking for help in selecting a new prop. I'm currently running a 14
1/4x 23p
3 blade that came on the boat from the factory. The boat is a 2003

Larson
SEI 190 (open bow runabout) with a 4.3 volvo sx sterndrive. It will turn
this prop 4600 rpms (4200-4600 reccomended by volvo at WOT) and 49 mph
according to speedometer at WOT.

This summer we have started doing alot of slalom skiing. Needless to say

it
is a bit lacking on power to pull up a 200# plus skier . I have been

looking
at 4 and 5 blade props but am at a loss as to what size should work best

for
me. Also is there a big trade off for power to loss of top end? I need
something that will be a good all around prop as we do alot of tubing

and
wakeboarding as well as just cruising around the lake.

I do not have a local dealer that will let me try out different sizes.

I'm
not afraid to spend some $ on a good prop, but dont want to experiment

with
sizes at the prices of these props.

Thanks for any help Steve








Tony Thomas September 10th 04 04:02 AM

You are exactly right. Dropping to a 21 will increase rpms by about 300 and
drop your speed. You would have to increase rpms by 500 to maintain the
same speed w/ a 2" drop in pitch.

However, something does not add up based on the numbers.
23 x 5400 / 1056 / 1.86 = 63 mph. That means you have a 60% efficiency.
Even if you had a 2:1 gearcase you still have a theoritical speed of 58 mph
which gives a 65% efficiency.



--
Tony
my boats at http://t.thomas.home.mchsi.com

"Short Wave Sportfishing" wrote in message
...
On Thu, 09 Sep 2004 01:00:54 GMT, "Tony Thomas"
wrote:

Not sure why you say this Rob. A 21 double cupped will definetly help on
the hole shot but will overrev by about 250 rpms. The double cupping

adds
bite and creates extra drag which reduces the rpms without adding pitch.

It
will also slow the boat down considerable due to the fact that your now
turning a 21 instead of a 23. Expect about 5 mph drop in top end if you
keep the rpms at 4600 (don't overrev).

As for the Torque Shift prop - I don't care for the maintenance of the

prop
springs and the cracked hubs and the stress on the lower unit. They do

work
but are not worth the money and maintenance costs.


I have a question for you.

My friend who has the engine problems also has a prop problem. He is
currently swinging a 14 1/2 x 23 on an Evinrude 200 FICHTand gets
about 38 mph at 5400 rpm WOT fully trimmed out. He can change pitch
which changes RPM but no relative increase in speed - in fact with a
21, he got 5700 RPM and lost four mph. The engine is properly
installed, etc.

Any idea why?

Later,

Tom





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