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Discussion Starter · #1 ·
ok, so I am trying to figure out the right prop, I know its experimentation, and I know that the different pitches cause a 200 RPM change per pitch BUT what I dont know is the difference in the blade #. Should I stick with a 4 blade? or go to a High 5? or a 3?

My boat is 26' long, has a 7.4L about 350HP, weighs just under 4000 lbs. right now it has a 14 x 18 4 blade stiletto that I am turning too fast. So I am thinking 21pitch but not sure how many blades. My goal is to increase my top end speed and still be able to get out of the hole.

Any suggestions?
 

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Sounds like a 21" 4 Blade Bravo would be worth a shot...
Throttle Up has helped just about everyone out here.
 

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I have a Mirage 21 pitch 3 blade in good condition. It is a pre-plus model without the inserts. Let me know if you are interested.
 

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If you don't NEED the extra blades then a 3-blade will be the fastest most times.

The difference between a Mirage Plus and standard Mirage is the Plus has more cup and will give you slightly less rpm. Many times the standard Mirage is faster.

I have tried quite a few 3 and 4 blade props on my boat and the standard Mirage is still the fastest prop. But, my propshaft is only 4.3" below the boat so the Mirage ventilates getting on plane and in the mid-range. The 4 blades bite much better getting on plane and cruising.
 

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I run the Laser II 21P. It seems to be perfect for me.

300HP 350 Mag with a 1.5 Alpha 1 57.3 GPS Turning 4700-4800 RPM's
 

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I think you should stick with the Mirage Plus 3 blade. But many have had great success with Bravo's and Hydromotive on the lighter boats.
 

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Leud Conduct said:
what do you think of a Laser II 21P?
The Laser II is a fast prop on the right boat but it is designed for smaller, lighter boats. Not sure it has the blade area to carry a 26' boat.

What speeds and rpm are you running with your current prop? And how deep is your propshaft?
 

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Still no one using the new "enertia" merc prop?

more blade are for holeshot and smooth ride... my outdrive drops about 7" below the keel, so my 4 blade eats alot of water and puts me on plane about 4-6 seconds quicker than a 3 blade with a full load.
 

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I just talked to hydromotive yesterday about a prop for my boat I went from a 454 built to 420 specs, to a stoker 496 bigger cam with 4-7 swap bigger valves bigger carb. I am running a 24 bravo 1 labbed I can spin it at will or cavitate the prop by just gassing the boat it will not hook up unless I am careful with the thottle. They reconmended a 5 blade and an increase in pitch to a 25. It is pretty pricey in my book over 1000.00 and they told me that it would have no effect on speed by adding an extra blade
 

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Hey, Leud Conduct
Did you get my reply via email? The prop will work on your boat. It is in good condition with no dings. If your prop is low in the water a 3 blade is usually faster. If your prop is closer to the water surface a four blade may be better. I still use a 3 blade only now I have a 25" mirage.
 

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Discussion Starter · #14 ·
Hey jeffswav

I didnt get your email send again. I'm not sure where I would measure to see how "low" my prop is. I think its down there at least a foot from the water line at the dock
 

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RSCHAP1 said:
Sounds like a 21" 4 Blade Bravo would be worth a shot...
Throttle Up has helped just about everyone out here.
I am pretty sure bravo only comes in even #'s, a 21 would be a lab. I have had good luck with rev+, but thats on my outboard, for him I would try the 21 mirage if the price is right, if not, a 21 mirage plus, then if he doesnt like the 3 blade, step back to a 20 or up to a 22 4 blade, depending on what RPM he gets off the 21 3 blade.
 

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Leud Conduct said:
Hey jeffswav

I didnt get your email send again. I'm not sure where I would measure to see how "low" my prop is. I think its down there at least a foot from the water line at the dock
Get your outdrive as level as possibe. Use a strait edge, (I used a 4' level) lay the level on the bottom of your boat, measure down to your propshaft centerline. Mine is deep about 8". From what I have read 3 blades work best for 6" or 8" deep drives. If you are interested I would take $250 plus shipping.
Thanks,
Jeff
 

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Discussion Starter · #17 ·
Ok, but what do you consider the bottom of my boat? Mine is moored now, not on a trailer. Do I set the level at the waterline? Top of the drive? Or the bottom of the V hull?
 

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Leud Conduct said:
Ok, but what do you consider the bottom of my boat? Mine is moored now, not on a trailer. Do I set the level at the waterline? Top of the drive? Or the bottom of the V hull?
You use the nottom of the v-hull so it has to be on a trailer or lift.
 
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