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"Lifting" Prop

Old 04-11-2004, 12:15 PM
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Daylight99
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Default "Lifting" Prop

Hi friends
My Miss Bud came with a 270 Prather prop but its clear that a lifting prop is needed on this boat. The boat has the G23 engine and I want to stay with a Prather brand prop. Does Prather make a lifting prop and if so which one would be best for a boat and engine?

Thanks for the help

Bob Russell
NAMBA #1090
Old 04-11-2004, 02:15 PM
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OLD_SLOW and in the WAY
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Default RE: "Lifting" Prop

the larger the "RAKE" (flatter or higher angle) of the blade the more lift you will get. imagine the blade slapping the water instead of slicing through it. an octura 967/3 blade has tons of lift and is typically a rigger prop. there are other out fits that make props like ABC or Propshop that have many configurations best to get ahold of someone who sells them for the right numbers. getting the correct balance (cg) is the most important then thrust angle so the hydro wont hop and when thats taken care of and you still need to get the tail up look at changin props. fopr example..... a 275 stainless prather is 7 mph slower than a prop shop 7016 /2 blade and its way slower than a 3015/3 blade ABC
Old 04-29-2004, 02:41 PM
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Default RE: "Lifting" Prop

Hi Bob:

Did you try any other prop yet. Please let me know.
Regards Joel
Old 04-29-2004, 05:39 PM
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Daylight99
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Default RE: "Lifting" Prop

Joel
I tried a Octura 1470 but all the boat wanted to do is cavitate and the speed dropped way off. I then went back to the Prather 270 but this time I shimmed the strut down about 1/8 to 1/4" and this correct the problem. The boat now ride's flat and the speed picked up as well, on a radar gun the boat was hitting 47mph with this setup.

Bob Russell
Old 04-30-2004, 09:17 AM
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Default RE: "Lifting" Prop

Hi Bob:

Thanks for the tips I will try it out and give you my results. My RC terminology is very poor; what is shimmed the strut down (is adding spacers between the strut base and the hull to increase the length resulting a deeper prop position?). Thanks for your advise.
Regards Joel
Old 04-30-2004, 09:19 AM
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Default RE: "Lifting" Prop

Hi Bob:

How is the best way to correct the CG issue. Thanks for the info. Regards Joel
Old 04-30-2004, 11:08 PM
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Default RE: "Lifting" Prop

ORIGINAL: Joel Antonio

Hi Bob:

How is the best way to correct the CG issue. Thanks for the info. Regards Joel

Once you shim down the strut and prop will lift the rear of the boat and the CG will no longer be an issue

Bob
Old 03-08-2005, 08:15 PM
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Default RE: "Lifting" Prop

Hi bob,what did you use as a spacer to shim the strut and did you have to rebend the stuffing tub to realign it with the strut???This sounds like a very interesting good idea.Also did it make it more stable doing this???

Brian
Old 03-09-2005, 07:37 AM
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Default RE: "Lifting" Prop

Hi all ... i too have shimmed the strut on my miss bud. I ended up leaving on the stock prop. Shimming the strut leveled the boat off nicely and gave me more speed. I also added a bh hanson pipe and header for more speed. Also a 1/4" flex. I am running low to mid 50's. I would really like to know what prop to put on her. please someone help. many thanks.
Old 03-09-2005, 07:39 AM
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Default RE: "Lifting" Prop

People have mentioned running a 6717 from prop shop... but that sounds like a bit much for a stock engine. I have seen plenty of guys running that size on mods.
Old 03-09-2005, 10:36 AM
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Default RE: "Lifting" Prop

there are two 6717 props one is a lifting and one is not....... dont ask me which is which
Old 03-09-2005, 01:14 PM
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4 Play Racing
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Default RE: "Lifting" Prop

What do yo mean by "shimming the strut"? Areyou trying to drop it deeper into the water? Not sure whay you are talking about.
Old 03-09-2005, 01:19 PM
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stoneenforcer
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Default RE: "Lifting" Prop

yeh . but that sounds like a lot of prop.... i wonder if a stock 26 can crank the rpm with it?? what about an octura 470 3 blade? thats closer to the stock prop. i don't know about it's pitch.
Old 03-09-2005, 01:24 PM
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Default RE: "Lifting" Prop

yeh . but that sounds like a lot of prop.... i wonder if a stock 26 can crank the rpm with it?? what about an octura 470 3 blade? thats closer to the stock prop...same dia... i don't know about it's pitch though. I wish someone could help....
Old 03-09-2005, 01:26 PM
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Default RE: "Lifting" Prop

will a 3 blade give me more speed?
Old 06-20-2005, 10:04 PM
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Default RE: "Lifting" Prop

[]I would skip the prather props and go with propshop, or one of the other manufacturs.
hydros normaly need some sort of lifting prop. You are creating some lift by lowering the prop shaft.I used to race hydros, riggers and still have a russel stark cracker box.
Old 06-21-2005, 07:07 AM
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Default RE: "Lifting" Prop

the x 470 three blade is a good prop for a stocker but for hydro's try a v967/3 it is the best lifting prop for a hydro

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