3 or 4 blade prop???

[Boston Predictor]

Here is a question for you guys...Why do some props have 4 or even 5 blades?
looking for a chopper propeller for my sportfire/merc, and wondering what will give me best top end?

 

[Boston Predictor]

Are more blades better?

 

[Mark]

On a small boat like a Spostfire a 3 blade will always be faster. Bigger boats can benefit from more blades as they may carry the weight better. Need 21' or more to make use of a 4 blade. The high speed 5 blades are expensive props engineered for offshore go fasts. I was talking to the owner of a 38' Donzi while in Texas. $295000 boat and he still had to reprop to 5 blades for another $4500 to get the thing over 75 MPH.

 

[Boston Predictor]

thanks Mark that clears things up for me.

 

[Boston Predictor]

Mark, Should I be looking for a big ear or small ear chopper?
I'm guessing small would rev higher...is that true?

 

[Mark]

BP
I'm no expert in this area, but this is what I know. The small ear chopper was designed for the inline Merc since it doesn't have as much low end torque. The big ear for the V6 since it could spool it up a little easier. They are known to be slower out of the hole. You probably already know it is not really an all around prop but built for top end. They slip at lower RPM because of the over the hub exhaust. I bet the guys on S&F could help you with this decision.

 

[Mark]

Oh and yes a small ear will rev higher in the same pitch. And there are guys who use them on V6's for that very reason. If you are asking around try to compare what guys are using with V6's on hulls of the same weight.... 8-900 pounds.

 

[illMATTic]

i think for what we are running a 28 would be the right prop.

 

[Reed]

I have a prop question, I have a 24 pitch chopper prop, and I just bought a 5 blade 24 pitch Mercury SS prop. Which prop will work the best on my 1979 trimate 2 ?? Reed

I think the chopper will my self

 

[175checkmate]

Run the 3 blade. Try the 5 blade but if it runs anything like the 4 blade I had it has to much blade area and makes the boat handle funny. To much grab in the prop.

 

[boatman4021]

The 5 blade Merc. was made for water sports and not high performance or top speed. I have a customer who took a 22" High Five off his bass boat and replaced it with a 23" 3 blade aluminum Hustler and gained 7mph and better hole shot. You be the judge. Boatman

 

[Reed]

Originally posted by 175checkmate:
Run the 3 blade. Try the 5 blade but if it runs anything like the 4 blade I had it has to much blade area and makes the boat handle funny. To much grab in the prop.

thanks I will try the 3 blade first

 

[Reed]

Boatman where do I find a protective case for my props when I travel??? looked on ebay no luck

 

[boatman4021]

Let me check and see if I can find them. I will let you know. boatman

 

[Reed]

thanks I have seen them just don't remember where

 

[supergenius74]

hey greg there is a guy on scream and fly that sells them, 15 bucks i think, I can't remember his name but if you search through the first few pages of buy and sell under accessories I think you will find it. shane

 

[pulse210]

Hi guys
Are you looking for a soft case or hard?

 

[captainmorgan]

4blade cleaver best yet

i was using a 3 blade 24 chopper, and my 2.5 merc pushes
my 21 enchanter atleast 5mph faster with the 4 cleaver.
seeing 75mph plus gps. ill send some pics of my smilemaker
soon.

 

[77trimate4]

I was turning a merc 18" pitch 4-blade on my 77 trimate4 improved the hole-shot alot; but had to watch the tach, it'd over-rev if i let it. We lost a few MPH on the top end. We tube and wakeboard behind it alot so the top end isn't as important as the holeshot.