setting new prop width

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sbeer
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setting new prop width

Post by sbeer »

Setting my prop width to 23 instead of 23 1/2. I want ot se what that does as far as wide open. Looking for 2850 loaded. Let u guys no. Mike
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dougl33
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Post by dougl33 »

Mike, What's your gear ratio?
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sbeer
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Post by sbeer »

Doug, Its 1.5 to 1. I presently run at wide open a little under 2800. Looking for 2850. Hopefully when the bottom is done I will pick up some speed and less drag. Having the props removed this week to reduce a 1/2 inch.
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Post by dougl33 »

I'm running 1.5:1. I've got 21d x 22p props with a number 5 cup.
Regards, Doug L.
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CB35
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Post by CB35 »

Mike that should do it. If your RPM's go too high put some cup in them. When I was fooling around with my 28B's props I found more cup is better then adding pitch. Cup seems to make the prop bite better. It was really noticeable on the gasser engines. Coming to the Rendezvous? I understand Clark's is starting the Fluke'in Fiesta up again this year!!!!!!
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sbeer
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Post by sbeer »

Charlie, got to check with the crew. As far as I know we will be there. Mike
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Post by stevefusco »

I still have the gas engines and need to get new props any suggestions? Where can I get them I am in Arizona Thanks, Steve
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BECCA ROSE
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Post by BECCA ROSE »

General Propeller www.gpcprop.com They will budge on their prices if you ask firmly. Good luck.
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Post by dougl33 »

Whenever I've needed new props I first narrow down to the exact set I want and then I do a google search. If you're not in a rush, you should have lots of options. If you wait until the beginning of the season you will have a hard time finding someone that actually has what you need in stock. Why do you need new props?
Regards, Doug L.
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Post by stevefusco »

20 years old and coroeded,\\looking at all options and trying to increase performance steve
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dougl33
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Post by dougl33 »

What is your current: 1. Prop Size (dia, pitch, blades, cup?) 2. Trans Ratio 3. Cruise RPM and speed. 4. WOT RPM and speed.
Regards, Doug L.
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Post by stevefusco »

Diameter 23 Pitch 25 Ratio 2.5-1 Cruise 3,000 rpm 18 knots WOpen 4,000 rpm 24 knots
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Post by dougl33 »

Steve, You didn't specify, but I'm assuming you have 3 blade props. If that's the case then that's pretty close to what the 1987 Bertram spec sheet shows. The only difference is that the sheet shows 26 inches of pitch. That being said, I wouldn't change the pitch as you're only getting 4K rpms. If you add anymore you'll be over loading the engines. Bertram shows 4400rpms with the stock prop size. Of course that's on a light boat with no enclosure. I really like Michigan props X series. The DJX is 3 bladed and the DQX is the 4 blade. These are Michigans skewed blade series. Even the 3 blades are really smooth.
Regards, Doug L.
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Post by stevefusco »

I do currently have the three blades any better with the 4 blades or should I stick with the 3?
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Post by dougl33 »

I'd stick with the 3 blade.
Regards, Doug L.
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