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Josh Assing
 
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Default prop fitting hell.


Here's all the info (for those not following along)

200hp v8 motor
outdrive
From factory with 19pitch prop
Engine RPM ideal range: 4200-4400

Had a 20 pitch 4 blade -- but reved too high.

Went to the local prop store -- they gave me a 23 pitch 3 blade.

Lots faster (on the range of 10 mph faster)

However, no has problems getting up to 4000 rpm, more like 3800

Based on that extreme jump; would a 21 pitch do me better? I don't want to keep
exchanging props (not to mention the expense of it -- ferry tickets and all) and
would like to start "using" the boat...

Thanks
-josh


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Bowgus
 
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My engine's WOT is about 4600 with the 21" prop ... but I never ... ok,
rarely ... run it at that. I normally use a 23" prop and cruise 2800 - 3000
rpm with a max of about 4200 rpm. What I'm saying is ... as long as my motor
isn't lugging, I'm ok with that ... I do not need to achieve max rpm etc
etc.
OT: It really is unfortunate that horsepower is the number that gets thrown
around when torque is really what it's all about ... which is not achieved
at max rpm ... imo.

So ... why not keep the 20" for when you and your 6 buddies are out ... and
use the 23" for lighter loads? And I suggest don't run WOT ... for very
long.


"Josh Assing" wrote in message
...

Here's all the info (for those not following along)

200hp v8 motor
outdrive
From factory with 19pitch prop
Engine RPM ideal range: 4200-4400

Had a 20 pitch 4 blade -- but reved too high.

Went to the local prop store -- they gave me a 23 pitch 3 blade.

Lots faster (on the range of 10 mph faster)

However, no has problems getting up to 4000 rpm, more like 3800

Based on that extreme jump; would a 21 pitch do me better? I don't want

to keep
exchanging props (not to mention the expense of it -- ferry tickets and

all) and
would like to start "using" the boat...

Thanks
-josh


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Tony Thomas
 
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The 21 will get you more into the power band and is probably the right prop
for what you want to do.
The 19 will probably put it right at 4400 or maybe a tad higher which will
provide good hole shot. This is why it came w/ this prop.
The 21 will be at 4100 to 4200 rpms and should be a good prop. My guess is
the 23 was very slow out of the hole.

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

"Josh Assing" wrote in message
...

Here's all the info (for those not following along)

200hp v8 motor
outdrive
From factory with 19pitch prop
Engine RPM ideal range: 4200-4400

Had a 20 pitch 4 blade -- but reved too high.

Went to the local prop store -- they gave me a 23 pitch 3 blade.

Lots faster (on the range of 10 mph faster)

However, no has problems getting up to 4000 rpm, more like 3800

Based on that extreme jump; would a 21 pitch do me better? I don't want

to keep
exchanging props (not to mention the expense of it -- ferry tickets and

all) and
would like to start "using" the boat...

Thanks
-josh


---
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Josh Assing
 
Posts: n/a
Default


Hmm. Good points. Well; another thing I thought is that I can't rely on HP
anymore; since it's a 14 year old motor.... so I doubt it's putting out what it
used to.

On Fri, 03 Sep 2004 00:52:19 GMT, "Bowgus" wrote:

My engine's WOT is about 4600 with the 21" prop ... but I never ... ok,
rarely ... run it at that. I normally use a 23" prop and cruise 2800 - 3000
rpm with a max of about 4200 rpm. What I'm saying is ... as long as my motor
isn't lugging, I'm ok with that ... I do not need to achieve max rpm etc
etc.
OT: It really is unfortunate that horsepower is the number that gets thrown
around when torque is really what it's all about ... which is not achieved
at max rpm ... imo.

So ... why not keep the 20" for when you and your 6 buddies are out ... and
use the 23" for lighter loads? And I suggest don't run WOT ... for very
long.


"Josh Assing" wrote in message
.. .

Here's all the info (for those not following along)

200hp v8 motor
outdrive
From factory with 19pitch prop
Engine RPM ideal range: 4200-4400

Had a 20 pitch 4 blade -- but reved too high.

Went to the local prop store -- they gave me a 23 pitch 3 blade.

Lots faster (on the range of 10 mph faster)

However, no has problems getting up to 4000 rpm, more like 3800

Based on that extreme jump; would a 21 pitch do me better? I don't want

to keep
exchanging props (not to mention the expense of it -- ferry tickets and

all) and
would like to start "using" the boat...

Thanks
-josh


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  #5   Report Post  
Josh Assing
 
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The 23 isn't bad out of hte hole... it is slower than the 20
I don't want to go to a 19 becuase the 20 over-reved.

Thanks
-josh


On Fri, 03 Sep 2004 02:18:29 GMT, "Tony Thomas" wrote:

The 21 will get you more into the power band and is probably the right prop
for what you want to do.
The 19 will probably put it right at 4400 or maybe a tad higher which will
provide good hole shot. This is why it came w/ this prop.
The 21 will be at 4100 to 4200 rpms and should be a good prop. My guess is
the 23 was very slow out of the hole.



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