85 Mistress 480 HP propping
#11
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Joined: Oct 2005
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From: Olmsted Falls,Ohio Marblehead,Oh
I guess I am looking for overall performance.. I don't see the boat running better then 64 on the best day now that I'm closer to dialing it in.... that's fine just want them to spin 5000 to to keep stress down on drives and such.
With the 23 mirage I cruise 3800@47. depending on waves... with 23 plus I get around 48. And that's not bad at all
I was curious if any 4 blade would keep me around same top end and gain any cruise speed over the 3 blades... most travel boats do best with 3 blades that I see...
With the 23 mirage I cruise 3800@47. depending on waves... with 23 plus I get around 48. And that's not bad at all
I was curious if any 4 blade would keep me around same top end and gain any cruise speed over the 3 blades... most travel boats do best with 3 blades that I see...
#12
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Joined: Oct 2005
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From: Olmsted Falls,Ohio Marblehead,Oh
I guess goal would be to keep engines at 5000-5100 and that gives me probably 64 Ish top end and then its seeing what gives me the most mid after that.... I don't wanna keep engines at 4700-4800 all the time...I am thinking for 3 blades the 23 mirage is perfect overall doing that....
#13
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Joined: Jul 2007
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From: Oneida Lake NY
However, the advantage of a 4 blade over a 3 for everyday boating is worth it IMO. The handle better, usually plane easier, and cruise speed/rpm is always better.
That being said I could be dead wrong with a boat of your vintage and weight, even more so the X dimensions in the older boats are traditionally lower which may not be the best for 4 blades.
I have a friend it an older 40 fountain. He switched his lowers to speedmasters on the trs and saw no gain using the same 3 blade cleavers, however gettting on plane became a challenge. In the end they ended up chopping the cav plates to run a bigger wheel, lower pitch cleaver 4 blade. Boat now hooks coming out so hard you would think it was on pavement. It performs everywhere better, and the slip numbers are so low it is hard to believe. Cruising and top speed went up 7 mph.
#14
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Joined: Oct 2005
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From: Olmsted Falls,Ohio Marblehead,Oh
I agree the 3 blade is gonna be faster... hydromotive said they could try to keep my top end and gain cruise with 4 blade.... but if I only get 2 MPH cruise going 4 blade to me the cost is not worth it....now if I gain 4 MPH then it is ......
Honestly I'm surprised the boat runs as good as it does with given power.....these mistress's weight over 10,000 I'm told but I have not had it on a scale yet... loaded with fuel and gear I bet I'm 10.5 or better... so 63 isn't that's bad really
Honestly I'm surprised the boat runs as good as it does with given power.....these mistress's weight over 10,000 I'm told but I have not had it on a scale yet... loaded with fuel and gear I bet I'm 10.5 or better... so 63 isn't that's bad really
#16
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Joined: Oct 2005
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From: Olmsted Falls,Ohio Marblehead,Oh
If I were to try a set given the speeds and rpm I posted, any idea where to start with pitch on a 4 blade?
#20
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Joined: Aug 2003
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From: Racine, Wisconsin
I'm pretty sure your going to need 22s if they make them. You could try 24s, they are probably easier to find but I think you will only spin around 4700-4800. I'm on the wrong computer to give a better answer.


