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Gas prices / prop changes?

RiverDave

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Most performance guys prop their boats to get the most mph out of them..

In my experience (not always but on my previous boats) Generally the props that run the biggest mph have pretty horrible slip numbers in cruising speeds etc..

I’m my Schiada I had a little (small diameter) four blade trophy that was the fastest prop I had at 72-73 mph…. But cruising at 50 it was over 4K rpm (43-4400)

I also had a 23 rev four blade (large diameter) for comparison 50 mph was 3500 Rpm’s effortlessly.. I’m talking like 1/2 the fuel consumption.


So I finally figured out the setup on these Avalons that would put mine in the 70’s…. Which is basically bravo fs 22’s that are labbed..

But I find myself leaving heavily towards getting a set of 19 pitch large diameter three blades called inertia’s by mercury which offer the best cruising fuel mileage you are going to get.. they are setup for heavy cruisers and center consoles for long range fuel economy.


So it got me to thinking.. Gas prices are getting ridiculous with no relief in site..

Anyone else planning on setting up their boats for better fuel economy? I would bet for cruising speeds (where we spend 90% of our time) with some prop changes and adjustments you could increase efficiency by a minimum of 10% from
Where you are at now and in some extreme cases upwards of 30-35%?

RD
 

hallett21

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I keep the trophy in the back seat but run the Bravo 1 23p because the mid range is so much better.

Trophy is fast but like your schiada it runs a pretty high rpm at 1/2 throttle
 
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Good Stuff

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I just tested a 28 Maximus last weekend. Had been running a 30p Bravo 1 before that. Dropped 1K RPM for planing and cruising and I’m pretty sure I will see some reduced fuel consumption as well.
 

coz

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I'm sure I'd use less gas if I didn't bring on 850+ lbs of ballast, but what fun would that be? 🤣👍
 

monkeyswrench

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Twin engine, 70mph, living room with a sound system that will rattle fillings loose...Yet worried about efficiency?

With the dollar loosing value by the day, burn it and have fun while you can. The cost of a pair of props may negate any fuel savings that may be attained in a given season. If you have access to spare props, not a bad idea. In the end though, if you build a 700hp/4spd hot rod, putting freeway fliers in the rear end seems to be counterproductive.

Don't ask me though, I have a Prius so I can eventually fill up my jet bote!
 

77charger

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My lil 350 mag in my 207 can’t complain. Might hit 60 on a perfect day but can do many miles on the water. Same 21p does it all.
 

retaocleg

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i ran a 4 blade in my blown lavey.........leave the last couple mph to the ballers
 

DLow

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If I want better gas mileage, I don’t change props… I let the 5500lbs of ballast out. 🤪
Other boat… speed is the only reason to be on the water. So, I’m screwed.
 

Hydroman55

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Always propped my big boats for mid- range efficiency not to cut gas use but drops RPM for longevity. Keep in mind, I lived on the Sac Delta and could lay down 100 plus miles in a day during the Summer.
Had B Blades rework a set of Bravo props per request and lost about 3-5 mph on the top end but dropped mid-range rpm around 500 at 60.
So 4500 at 60 before rework and 4000 at 60 after.
As Dave said …slippage is part of the equation among other factors.
 
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pkrrvr619

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Funny, I just made a deal with a member here for a 32p to squeeze some more mph out of my boat.

However with gas prices slapping the 28 on is seeming more like a better option come mid summer
 
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JUSTWANNARACE

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I was just thinking of Pops' Bayliner Capri with the 4.3. 3 weekends on a tank!

Vortec V6 in my brothers new boat. Still runs right at 50mph and pretty good on fuel being a "suck-n-blow"
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MK1MOD0

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I would definitely change them out Dave. Personally....... a 70 mph pontoon is as worthless as tits on a bull. Only one person having fun at that speed on a pontoon. Being able to cut your fuel consumption by say 15-20 percent will really add up at the end of the season. And... your crew will enjoy themselves just as much
 
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throttle

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RD, I ran that Mercury Inertia. I felt it was efficient at lower RPM's, but once you get it over 5000rpm's I feel you are going to see the gauge drop anyway.
 

4Waters

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I run a 19p 4 blade, 67-68 at 5k rpms but I would like to get a little better low end @hallett21 has a 19p High5 that I'm going to try out, I know I will lose a little top end and pick up some bottom end but what do you guys think that extra blade will do for mid range. I know the High5 is slightly smaller in diameter than a 4 blade.
 

hallett21

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I run a 19p 4 blade, 67-68 at 5k rpms but I would like to get a little better low end @hallett21 has a 19p High5 that I'm going to try out, I know I will lose a little top end and pick up some bottom end but what do you guys think that extra blade will do for mid range. I know the High5 is slightly smaller in diameter than a 4 blade.
Grabbing them today for you 👍🏻👍🏻
 

Ace in the Hole

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Just inform the kids….


View attachment 1118161
No joke...the single biggest suck on fuel there is for my boat. Amex was calling hitmen for quotes over that trip 🤣😂

To answer dave's original question... No, I'm actually borrowing a couple props for testing to try too get a few more MPH out of the boat. Biggest thing im going to do for fuel economy is just keep the RPMS lower and not run around as much. I ran most of Friday at 3500 rpms which is a big difference in fuel vs 4800 etc on mine.
 

Shlbyntro

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what do you guys think a pair of 26P vented powertechs are worth?😁
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RiverDave

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RD, I ran that Mercury Inertia. I felt it was efficient at lower RPM's, but once you get it over 5000rpm's I feel you are going to see the gauge drop anyway.
Well that’s what I was saying, having a set of efficient cruising props
 

riverroyal

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I have a inertia on my avalon. The only way i found to get decent mph is too slow down .
The verado eats gas wide open.
Above 4000rpm and the prop wont matter
Id save the money and leave them alone.
I do have one more hole available to raise the motor. I might try that
 

Willie B

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… Up at Lake Oroville…All I had to do to experiment with props …just take my bronze three blade from my 1963 Hallett and have PB’s Prop shop do a little experimenting👍

… The two blade steel prop on my 18 foot Sanger Circle, Runnerbottom… was perfect from the day I bought the boat… The first two blade I’ve ever seen that did not vibrate… since I had to run VP 110 octane race guess I never worried too much about fuel mileage…lol…
 

throttle

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Well that’s what I was saying, having a set of efficient cruising props
Its the new “Hill Propeller”. I had this made before selling the boat, worth looking into if you gonna have something made 👍

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farmo83

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I gave alexi a boat loaf of money for an efi setup last year. That's my contribution towards better economy.
 
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