Just bought a 4 blade prop

RubberFrog

Rear Admiral
Joined
Apr 9, 2005
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I just bought a Vortex Aluminum 4 Blade 14.5" dia x 18" pitch from iboats for under $115 delivered.

It is replacing a 14.5 x 19 3 blade prop. My WOT is right at 4800 with my existing prop. I am anticipating my WOT to be some around 4600 with the cupping on the new prop. That should keep me nicely between my WOT range of 4400 - 4800.

I will give lots of feedback as I test it out.
 

Zeusdafreak1

Seaman
Joined
Jun 28, 2006
Messages
62
Re: Just bought a 4 blade prop

Keep us posted. I am very interested in your results. Good luck. Hope it performs as well as you expect.
 

Tail_Gunner

Admiral
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Jan 13, 2006
Messages
6,237
Re: Just bought a 4 blade prop

:cool:
I just bought a Vortex Aluminum 4 Blade 14.5" dia x 18" pitch from iboats for under $115 delivered.

It is replacing a 14.5 x 19 3 blade prop. My WOT is right at 4800 with my existing prop. I am anticipating my WOT to be some around 4600 with the cupping on the new prop. That should keep me nicely between my WOT range of 4400 - 4800.

I will give lots of feedback as I test it out.


:cool: have you vented this prop, i know your naturally aspirated are you going to spred the wealth......:eek:
 

Maps

Petty Officer 2nd Class
Joined
Feb 28, 2007
Messages
131
Re: Just bought a 4 blade prop

I ordered the exact same size Alu prop.
My original prop was also a 3 blade 14 1/2 19
 

RubberFrog

Rear Admiral
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Apr 9, 2005
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Re: Just bought a 4 blade prop

Have you tried it out yet? What effect did it have on your WOT?
 

Apocalypso

Cadet
Joined
Jun 6, 2007
Messages
8
Re: Just bought a 4 blade prop

I have the same 14.5 X 19 prop on a Four Winns 190 Horizon with a 4.3 VP SX drive. I have been conducting an exhuastive search and have settled on a 4 blade 18 pitch prop to bring down my WOT (4900) and increase control. Since I haven't purchased it yet, I am very interested in your results.
Thanks, Jim
 

tommays

Admiral
Joined
Jul 4, 2004
Messages
6,768
Re: Just bought a 4 blade prop

i bought the same one in 14 X 20 for my 19' 3.0 powered boat


It has really worked out well compared to the 3 blade 14 X 19


I am able to stay on plane at about 400 less rpm in rough water and it holds speed in these conditions much better


My wife who hates getting pounded buy chop loves it and noticed i did NOT have to keep makeing so many small RPM adjustments


Tommays
 

Maps

Petty Officer 2nd Class
Joined
Feb 28, 2007
Messages
131
Re: Just bought a 4 blade prop

Have you tried it out yet? What effect did it have on your WOT?
I will receive it at the beginning of next week. I'll post my results as soon as I make the switch.

So far my WOT is not bad. 48 mph close to 4900rpm. With a 4 blade Im expecting better handling and better on plane. Not that my 3 blade is bad but I can still bring down my rpm cause my range is 4600-5000rpm

I do not expect to gain speed at WOT however it would be a bonus
 

RubberFrog

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Apr 9, 2005
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Re: Just bought a 4 blade prop

Well, I tried out the prop over the last few days and I am definately impressed with the results.

Surprisingly, my WOT stayed right at 4800. Exactly where it was with the 14.5 x 19 3 blade. Holeshot was dramatically improved. Even with 6 adults on board, it still leapt onto plane better than it did with 4 adults and the 3 blade.

Slow speed handling, specifically around the dock, was much better. Especially when using reverse. It was so responsive that docking almost became a pleasure.

There was absolutely no blow out in heavy cornering. This made the tube rides a lot more exciting as we could really sling shot the "tough guys" from side to side. Previously, my 3 blade would lose 20 - 30% of its speed when aggressively turning.

The boat rode much higher on plane than previously. This may be my only complaint. I had to trim out a little less to avoid some slight chine walking. Nothing drastic though.

My top speed went from just over 45 with the 3 blade, down to 42 mph (gps). It's difficult to say how accurate those speeds really are, because I was on a tidal river and I did not monitor the tides. I did take the speeds going down river, but the tide can change the water speed by as much 5 mph. I've gotten as fast as 48 with the 3 blade previously, but never with 6 adults!

Overall impression: I love this prop for watersports and/or lots of passengers. It was a real pleasure at the dock. If I am in for a go fast day, I might look into a SS 3 blade with more cupping.
 

Maps

Petty Officer 2nd Class
Joined
Feb 28, 2007
Messages
131
Re: Just bought a 4 blade prop

Today I just switched my 14.5X19 3 blade prop for my new 14.5X18 4 blade prop.
Because of the bad weather me boat is still in me drive way !

I'll post my results soon
 

javsam

Chief Petty Officer
Joined
Aug 24, 2005
Messages
421
Re: Just bought a 4 blade prop

rubberfrog, can you give me a link to where you can get a 4 blade prop for 115. I looked on Iboats and couldnt find it.thanks
 

Maps

Petty Officer 2nd Class
Joined
Feb 28, 2007
Messages
131
Re: Just bought a 4 blade prop

From a 14.5X19 3 Alu blade to a 14.5X18 4 Alu blade prop

I lost 3mph on top speed (50 to 47mph) at 5000rpm

Cruise speed (30mph) I'm at 3200rpm was at 3000rpm

Plane time increased like at bat out of hell and low speed handling improved considerably. Also trim switch is way more sensitive.

I have a V8 5.0Gxi penta drive (270hp) bowrider is around 3000lbs 19'. I expected more top end from this engine. I have a V-type hull 18deg of deadrise. The boat handles extremely well in 1-2 feet chop.

If my rpm's increased by +-300 will I burn more fuel with this set up ?
 

RubberFrog

Rear Admiral
Joined
Apr 9, 2005
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Re: Just bought a 4 blade prop

If my rpm's increased by +-300 will I burn more fuel with this set up ?

Not necessarily. Your engine may be under less of a load even though the rpm's are higher. Higher rpm's don't necessarily mean you're using more fuel. Remember that the boat is riding higher on plane and that means less drag.
 

ASCTLC

Seaman
Joined
Apr 21, 2007
Messages
57
Re: Just bought a 4 blade prop

From a 14.5X19 3 Alu blade to a 14.5X18 4 Alu blade prop

...Plane time increased like at bat out of hell ...

Although you lost a little top end speed it sounds like you are satisfied with the improvement in low-mid range performance enough that you find the speed loss at the top end a justified sacrifice for the low range improvements? Also, when you state "Plane time increased like a bat out of hell...", are you meaning that it planes out of the hole much faster or did the time to get on plane actually increase?

Thanks,
Andy
 

Maps

Petty Officer 2nd Class
Joined
Feb 28, 2007
Messages
131
Re: Just bought a 4 blade prop

"Plane time increased like a bat out of hell...", are you meaning that it planes out of the hole much faster or did the time to get on plane actually increase?

Thanks,
Andy
Sorry I was trying to say that the boat definitely planes higher and more rapidly. Thus I will not be going back to my 3 blade prop.
And yes the improvements at low range justifies the 3mph loss at top end.

Now I'm curious to know what an SS prop might do...
 
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