All,

I have recently purchased a 1993 Stratos 274 DC bass boat, 17.5' long.
It came with what I was told
was a stock motor -- 150 HP Evinrude.

The seller had changed the prop to a spare he had -- 25 pitch, 13.5",
4 blade propeller. The boat
now has a hole shot that takes a long time, bow wayyyyyy up until you
nurse back power a bit to
bring it on plane. It generates 4400 rpms and reaches about 50 mph via
gps (MFG range is 4500-5500 RPM at WOT). It has a jackplate and
I've raised it from about 6 inches to about 4 currently.

Does anyone know what the original prop would be? If not, does anyone
have any advice about
what I should try next?

What I've read online suggests this:

*get RPM's up first -- and that reducing pitch by 1" = 200 RPM's on
average. So I'm thinking dropping
pitch by 3-4" is the right place to be, or in my case either a 21 or
22" prop.

*blades -- 3 or 4?? I have no idea what the difference might be.

*diameter: I have no idea.


Thanks much!!

Please reply to

I have a 225 ficht on a 26' v bottom aluminum workboat and at 6000rpm the 3
blade only gave me around 35mph and the 4 blade again at 6000 gave me 42
mph, I was amazed because I thought the 3 blade would give a higher top
speed.

"bleezle" wrote in message
oups.com...

All,

I have recently purchased a 1993 Stratos 274 DC bass boat, 17.5' long.
It came with what I was told
was a stock motor -- 150 HP Evinrude.

The seller had changed the prop to a spare he had -- 25 pitch, 13.5",
4 blade propeller. The boat
now has a hole shot that takes a long time, bow wayyyyyy up until you
nurse back power a bit to
bring it on plane. It generates 4400 rpms and reaches about 50 mph via
gps (MFG range is 4500-5500 RPM at WOT). It has a jackplate and
I've raised it from about 6 inches to about 4 currently.

Does anyone know what the original prop would be? If not, does anyone
have any advice about
what I should try next?

What I've read online suggests this:

*get RPM's up first -- and that reducing pitch by 1" = 200 RPM's on
average. So I'm thinking dropping
pitch by 3-4" is the right place to be, or in my case either a 21 or
22" prop.

*blades -- 3 or 4?? I have no idea what the difference might be.

*diameter: I have no idea.


Thanks much!!

Please reply to

"mark" wrote in message
...
I have a 225 ficht on a 26' v bottom aluminum workboat and at 6000rpm the 3
blade only gave me around 35mph and the 4 blade again at 6000 gave me 42
mph, I was amazed because I thought the 3 blade would give a higher top
speed.

Were they the same pitch and diameter?


"bleezle" wrote in message
oups.com...

All,

I have recently purchased a 1993 Stratos 274 DC bass boat, 17.5' long.
It came with what I was told
was a stock motor -- 150 HP Evinrude.

The seller had changed the prop to a spare he had -- 25 pitch, 13.5",
4 blade propeller. The boat
now has a hole shot that takes a long time, bow wayyyyyy up until you
nurse back power a bit to
bring it on plane. It generates 4400 rpms and reaches about 50 mph via
gps (MFG range is 4500-5500 RPM at WOT). It has a jackplate and
I've raised it from about 6 inches to about 4 currently.

Does anyone know what the original prop would be? If not, does anyone
have any advice about
what I should try next?

What I've read online suggests this:

*get RPM's up first -- and that reducing pitch by 1" = 200 RPM's on
average. So I'm thinking dropping
pitch by 3-4" is the right place to be, or in my case either a 21 or
22" prop.

*blades -- 3 or 4?? I have no idea what the difference might be.

*diameter: I have no idea.


Thanks much!!

Please reply to

Bishoop wrote:
"mark" wrote in message
...

I have a 225 ficht on a 26' v bottom aluminum workboat and at 6000rpm the 3
blade only gave me around 35mph and the 4 blade again at 6000 gave me 42
mph, I was amazed because I thought the 3 blade would give a higher top
speed.


Were they the same pitch and diameter?



Of course not.

Rob

"trainfan1" wrote in message
et...
Bishoop wrote:
"mark" wrote in message
...

I have a 225 ficht on a 26' v bottom aluminum workboat and at 6000rpm the
3 blade only gave me around 35mph and the 4 blade again at 6000 gave me
42 mph, I was amazed because I thought the 3 blade would give a higher
top speed.


Were they the same pitch and diameter?



Of course not.

Rob

I don't belive so either. With the facts as they were presented, the laws of
physics would have to be rewritten.

In probably 99% of all installations a three blade with the same pitch (all
other things being equal) will be "slightly" faster than a four blade.

Bishoop wrote:
"trainfan1" wrote in message
et...

Bishoop wrote:

"mark" wrote in message
...


I have a 225 ficht on a 26' v bottom aluminum workboat and at 6000rpm the
3 blade only gave me around 35mph and the 4 blade again at 6000 gave me
42 mph, I was amazed because I thought the 3 blade would give a higher
top speed.


Were they the same pitch and diameter?



Of course not.

Rob


I don't belive so either. With the facts as they were presented, the laws of
physics would have to be rewritten.

In probably 99% of all installations a three blade with the same pitch (all
other things being equal) will be "slightly" faster than a four blade.



I am no expert, But I think the 3 blade would run faster with equal
pitch. This is due to the added resistance of pushing the forth blade.
On my old cuddy (gee I miss it :-) I had a 17 on it and heard the boat
would plane at slower speed with the four blade. Merc suggested since I
was trying to keep the rpms the same to go to a 16 inch pitch four blade
as a direct replacement for a 17 three blade.

Tried it out and the boat did plane at a faster rate, I am not a speed
demon so I really did not try to see where the top end was.

Retired the four blade to the "spare" shelf as it made holding the bow
up rather difficult - ie the boat ran with the stern up high and
trimming it would not help.

Your mileage may vary, this boat had a wide stern for it's length and 18
degree deadrise at the transom.

Capt Jack R..

bleezle wrote:

All,

I have recently purchased a 1993 Stratos 274 DC bass boat, 17.5' long.
It came with what I was told
was a stock motor -- 150 HP Evinrude.

The seller had changed the prop to a spare he had -- 25 pitch, 13.5",
4 blade propeller. The boat
now has a hole shot that takes a long time, bow wayyyyyy up until you
nurse back power a bit to
bring it on plane. It generates 4400 rpms and reaches about 50 mph via
gps (MFG range is 4500-5500 RPM at WOT). It has a jackplate and
I've raised it from about 6 inches to about 4 currently.

Does anyone know what the original prop would be? If not, does anyone
have any advice about
what I should try next?

What I've read online suggests this:

*get RPM's up first -- and that reducing pitch by 1" = 200 RPM's on
average. So I'm thinking dropping
pitch by 3-4" is the right place to be, or in my case either a 21 or
22" prop.

*blades -- 3 or 4?? I have no idea what the difference might be.

*diameter: I have no idea.


Thanks much!!

Please reply to



Does the prop have black rubber plugs on the side? If it does, you
might want to try venting it. Google the group for plenty of info on that.

You can also try the Mercury prop selector, the brand makes little
difference:

http://sites.mercurymarine.com/porta...che ma=PORTAL

Dan