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Fuel mileage

"It's amazing what a small

"It's amazing what a small change in deadrise angle will do, both good and bad. I've got a 24.5 deg deadrise hull, running twin 454's. There is very little evidence of planing, even at top speed (30 kts). Almost no bow rise, ever. At 20kt cruise, still 2/3 or more of length of the hull is still in the water. One engine operation is poor, with anything over 1500 rpm, pretty much wasted energy. If I have to travel with one engine, i'm going 8 kts. However, 18 kts is possible, sitting down, in 6 foot seas. That's why I have it..."
 
"Mine is a 1966 28ft(30&#3

"Mine is a 1966 28ft(30'8") Californian Express cruiser weight aprox 10,000 twin 350's aprox 270hp each Borg Warner Velvet Drives 1:1 ratio, 3 bladed props. Not sure the size They didnt look very big when I hauled out 2years ago and looked them over. I usually operate in the following RPM/KNOT ranges 2200/14, 2400/18, 2500/20 she,ll do over 4,000 however the engines are older, hours unknown so I keep her below 3,000 RPM she runs fast enough at those ranges and seems to like it in that rpm range."
 
Your props are probably about

Your props are probably about 14 inch diameter. Good numbers on the rpm vs. speeds.

Jeff
 
"Ted; My boat is Cary 32, sp

"Ted; My boat is Cary 32, sportfish with a marlin tower. Cruise 3200 @ 21kts @ 22g/h, when light. Engines are 1975's, one with orig pistons. I routinely run at WOT for a couple of minutes, after most outings. I feel it "tests things out", like the cooling system, fuel system, barnacle status and ignition system. Any lack of power issues will surface quickly at WOT. Lots of people are timid about that, I'm not. If something is close to letting go, I want to find out close to home on my terms, not offshore in a foreign country. Great way to find out about near clogged fuel filters, and one time, a big end bearing!"
 
Agree with "diver dave&#34

Agree with "diver dave" on the WOT test.
That is how I sized my props and found other issues!

Problem with WOT method for sizing is: When do you test it (full weight or tanks half empty for example) I use full weight for WOT. Your RPMs go up as your weight goes down.
 
"If you have both a GPS and a

"If you have both a GPS and a fuel flow meter, then you can test at cruising speeds. I do this every time I plane off. All three things: speed, rpm and GPH must be "normal" or I start looking. The only joker in the deck is current: I have to take into account which way the river is flowing, and how fast.

Jeff

PS: If I was forced to do this at WOT, that flowmeter would have paid for itself long ago!"
 
"Jaimes click on the "Uplo

"Jaimes click on the "Upload Attachment" button below the formatting box. Type a description for your attachment then locate the picture you wish to upload from your computer. Then click the upload button. I am not sure what the maximum file size you can upload is but if you exceed it then the program will notify you.

From the help file:

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Upon posting, you are prompted for an image file to upload. Images must be either GIF or JPEG format. Images must be saved on your hard disk. Your browser must support form-based file upload (Netscape Navigator 2.0+ and Internet Explorer 4.0+ support this; IE 3.02 will also work provided that you have installed the file upload patch)."
 
"Jaimes click on the "Uplo

"Jaimes click on the "Upload Attachment" button below the formatting box. Type a description for your attachment then locate the picture you wish to upload from your computer. Then click the upload button. I am not sure what the maximum file size you can upload is but if you exceed it then the program will notify you.

From the help file:

Tag Description

Upon posting, you are prompted for an image file to upload. Images must be either GIF or JPEG format. Images must be saved on your hard disk. Your browser must support form-based file upload (Netscape Navigator 2.0+ and Internet Explorer 4.0+ support this; IE 3.02 will also work provided that you have installed the file upload patch)."
 
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