Figuring out what prop to run?

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Joenagy

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Dec 27, 2015
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I Need some help ................ Not Medical supervised Help. LOL

So Ive got a box full of props and a room full of boats. How to I figure what prop to run? I need some sort of cheat sheet.

Joe
 
L

lohring

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That's a great resource. If you are interested in more look at the series of articles on props in the October 2013, April 2014, and March 2015 issues of the NAMBA Propwash.

Lohring Miller
 

PaulHail

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Mar 30, 2017
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357
I find searching intlwaters via google to be a pretty good way to find out tips on props for a given hull.
 

shoboat

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Jun 23, 2002
Messages
6,990
Joe, and Others,

With the newer style (Some are 3 years old now) ABC Propellers here are some general ideas for heat racing:

21-Tunnel:

1417, 1419, 1514,1515, 1614

45-Tunnel:

1815, 1817,1915

21-Mono:

1614/3-15*-65% Chopper

Newest 1614/3-15*-60% Cleaver

45-Mono:

1914/3, 2015, 2115, 2116

Sport 40:

1914/3, 2015, 2115, 2116

1/8th Scale:

2315

Newest 2315/3-23*-47

12-Hydro:

1415, 1417, 1419, 1514,1515, 1517, 1519

21-Hydro:

1715,1716, 1717, 1815, 1817, 1914, 1915

45-Hydro:

2117, 2119, 2215, 2217, 2219

67-Hydro:

2417, 2419, 2515, 2517, 2519

90-Hydro:

2617, 2619, 2717, 2719

Twin Hydro:

2717, 2717/3, 2719, 2817,2819

Just a rough ballpark for most of the Nitro classes.

The rake that works well on all of these is a: 19 degree rake and 38% blade area

The three blades are 15 degree rake and either 60% or 65% blade area,

or some newer ones coming out have 47% blade area also.

Thanks For Reading Fellas,

Mark Sholund
 
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Michael Costanzo

Well-Known Member
Supporting Member
Joined
Jan 7, 2009
Messages
1,953
Joe, and Others,

With the newer style (Some are 3 years old now) ABC Propellers here are some general ideas for heat racing:

21-Tunnel:

1417, 1419, 1514,1515

45-Tunnel:

1815, 1817,1915

21-Mono:

1614/3 Chopper Style

Newest 1614/3 Cleaver Style

45-Mono:

1914/3, 2015, 2115

Sport 40:

1914/3, 2015, 2115

1/8th Scale:

2315

Newest 2315/3

12-Hydro:

1415, 1417, 1419, 1514,1515, 1517, 1519

21-Hydro:

1715,1716, 1815, 1817

45-Hydro:

2117,2215, 2217, 2219

67-Hydro:

2515, 2517, 2519

90-Hydro:

2617, 2619, 2717, 2719

Twin Hydro:

2717, 2719, 2817,2819

Just a rough ballpark for most of the Nitro classes.

The rake that works well on all of these is a: 19 degree rake and 38% blade area

The three blades are 15 degree rake and either 60% blade area

or some newer ones coming out soon will have 47% blade area also.

Thanks For Reading Fellas,

Mark Sholund
hi mark, maybe you could give a little insight in trying to compare RAKE and BLADE AREA between prop makers...like i run a lot of Prather props.so when i look at the ABC prop chart i have sort of an idea of how to compare the two.thanks,mike.
 

shoboat

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Jun 23, 2002
Messages
6,990
Mike,

Prather or Octura do not use Blade Area Ratio or Rake angles like ABC.

You get what you pay for. You can calculate it if you have a bunch of

time on your hands Mike? ABC Propellers are designed with an expensive

software package that allows Jim to make whatever design he wants too.

Compare with diameter and pitch ratio and you will be pretty close. Prather

is mostly a 1.5 pitch ratio, and Octura has many to choose from.

Enjoy The Weekend,

Mark Sholund
 

Michael Costanzo

Well-Known Member
Supporting Member
Joined
Jan 7, 2009
Messages
1,953
Mike,

Prather or Octura do not use Blade Area Ratio or Rake angles like ABC.

You get what you pay for. You can calculate it if you have a bunch of

time on your hands Mike? ABC Propellers are designed with an expensive

software package that allows Jim to make whatever design he wants too.

Compare with diameter and pitch ratio and you will be pretty close. Prather

is mostly a 1.5 pitch ratio, and Octura has many to choose from.

Enjoy The Weekend,

Mark Sholund
hi mark,thank you for the reply. i am using the Dia/Pitch method now and that is what i will stick to.have a great weekend also,mike.
 

Dennis Somers

Well-Known Member
Joined
Oct 20, 2011
Messages
141
Terry, get in touch with Bob English @ kneedrag10@yahoo.com and try an ABC 2714-15-50 (2), or an ABC 2716-15-50 (2). Bob thins, sharpens, and balances these props for $50 and ships for $5.

There are a few other simple things you can do for more speed on that boat. Don't use a velocity stack on the carb. Shorten your Zipp pipe up on the header as much as you can without it leaking at the header bend. And YOU MUST provide a lot of air into and out of, that sealed hatch. Gas motors suck a lot of air and the enclosed pipe heats and expands that air. Get fresh/cool air IN and hot air OUT.

And stuff the hull with pool noodles, and glue some floatation under the hatch.
 
Joined
Jun 23, 2019
Messages
10
I believe after today I am on the right track. Our club's engine builder finished the mods on my stock motor so that along with Dennis's helpful suggestions pushed this Cat to 65.1 mph today! Bob English did a great job with this 2714/15 that he sent me.
 

Attachments

Joined
Jun 23, 2019
Messages
10
Stock motor mods...piston is modified and lightened, the transfer ports are reshaped and bigger, the intake port and the exhaust port is bigger and retimed, the squish is set and burn chamber is larger, the crank is trued and the carb is modified to. 20 mph gain. Thank you Steve! (SS Racing)
 
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