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TRI TOONS, 3 OR 4 BLADE PROP TRUTH AND FACTS....

FlyByWire

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Took a stroll down to the springs with the fam for a big stick and some dinner.

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Where I’d like to cruise. Damn near wrung ourt
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WOT. Pegs to max RPM and stays there till the boat stops accelerating.
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What concerns me is the damn 20 gallons an hour at what I thought was my cruising speed. [emoji15][emoji15][emoji15]
 

Lavey29

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This is another drawback to high revving outboards that dont have the torque of a big block.
 

HavaToon

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Took a stroll down to the springs with the fam for a big stick and some dinner.

View attachment 774190

View attachment 774191

Where I’d like to cruise. Damn near wrung ourt
View attachment 774192

WOT. Pegs to max RPM and stays there till the boat stops accelerating.
View attachment 774194

What concerns me is the damn 20 gallons an hour at what I thought was my cruising speed. [emoji15][emoji15][emoji15]

You’re at 6630, a little under max RPM of 6800. I’d bet you can up the pitch and move the motor up gaining more overall not to mention a better cruise RPM/fuel burn.

Offer is still open to try my REV 4 19P. Be in Havasu this weekend.

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FlyByWire

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You’re at 6630, a little under max RPM of 6800. I’d bet you can up the pitch and move the motor up gaining more overall not to mention a better cruise RPM/fuel burn.

Offer is still open to try my REV 4 19P. Be in Havasu this weekend.

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Do I even want to know the labor cost in moving the engine up a hole? Lol. On mine, There’s only one hole in each direction it can be moved.

I don’t think I can put the boat in the water this weekend, but if you want to try the 17 3 blade I’ll have it off tomorrow for the 20 hour anyway...!
 

HavaToon

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Do I even want to know the labor cost in moving the engine up a hole? Lol. On mine, There’s only one hole in each direction it can be moved.

I don’t think I can put the boat in the water this weekend, but if you want to try the 17 3 blade I’ll have it off tomorrow for the 20 hour anyway...!

Fallon did it for me for $20 during my last service to move the motor. I have since done it myself with a floor jack, remove the bolts in the holes and only loosen the ones in the slots.

First I’d suggest just trying the prop before moving the engine. If you like it or it’s close to RPM you need them move the motor. Better to do adjustments separately.

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2FORCEFULL

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Took a stroll down to the springs with the fam for a big stick and some dinner.

View attachment 774190

View attachment 774191

Where I’d like to cruise. Damn near wrung ourt
View attachment 774192

WOT. Pegs to max RPM and stays there till the boat stops accelerating.
View attachment 774194

What concerns me is the damn 20 gallons an hour at what I thought was my cruising speed. [emoji15][emoji15][emoji15]
Good job buddy, now something to work with, and something to look forward to...

first,.. here's where you are at...and not as bad as I first thought..

prop slip…@ 41.1 slip= 16% … @45.6 slip = 11%... @ 52.7 slip =8%

so here what to expect ...if you go to a 17p 4 blade using your same cruise speed of 41.1 mph,and same slip of 16%, your rpms drop to 5256 rpms...but here's where it might get way better...if the 4 blade bite is as calculated...your rpms @ 8% would drop to 4856 rpms..
that's almost a 800 rpm drop with just a 1'' pitch prop change.... the hard to find part here is the torque curve of your motor ,..marine motors are very hush hush when it comes to torque...but...on a 24' pontoon, the Evinrude 250 ho will spin a 19p four blade @ 4300 rpms, 39.7 mph, 5 % slip...@ only 12.3 GHP...

it wouldn't take much to get a lot of results from your set up...

I'm pretty sure of this,.... that motor needs a lot of rpms to make the advertised hp...but, when in a more economy rpm, the power drops...as with honda… all three motor are the same... 200hp,225hp,250hp,...they tune the 250 hp to get the advertised hp @ 5800 rpm, while the 200hp & 225hp @5500 rpm
 

2FORCEFULL

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Fallon did it for me for $20 during my last service to move the motor. I have since done it myself with a floor jack, remove the bolts in the holes and only loosen the ones in the slots.

First I’d suggest just trying the prop before moving the engine. If you like it or it’s close to RPM you need them move the motor. Better to do adjustments separately.

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great post, I always do just one change at a time....that way I know what direction the change went..being lazy, and not wanting to run back and forth to the prop shop,and to make sure of my prop selection..I bought 15p,17p18p & 19p,I also have both 4 and 3 blades...
I might be in havasu Friday,... but for sure sat. thru Monday..
 

2FORCEFULL

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so here another point,... the Evinrude is a torque monster, lets say it spins a 19 pitch prop.... the same 30 mph will be done at only 3600 rpms..... you would need a vacume gauge to measure the load on the motor...or make sure it will still spin to the max 6000 rpms....

but lets say now you went to a 4 blade 17p to bring the slip down... to 8%... the same 4000 rpms would net 32 mph...
when I did this actual on the water test...w/17p 4 blade...4030 rpms = 31 mph...@12% slip...and with the 19p 4 blade..3500 rpm = 29.7 mph,@ 13% slip... but only 8.4 GPH...
 

HavaToon

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@2FORCEFULL

Here’s where I’m at motor height. Should I leave it or go up my max 2 holes. When I got the boat the motor was buried on the lowest hole, I already moved it up 2 to the middle which helped a lot.

Splash plate is about 1/4-1/2” above notch and cavitation plate is about 2.5” below notch.

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HavaToon

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Prop shaft is 4.5” below bottom and 10” below the notch
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2FORCEFULL

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I would say try up one more hoLE at a time... the only thing to watch for would be loss on hole shot, that and one of my concerns is what would happen if the front was loadd too much...the notch is like sues godfrey, and the drive gets plenty of water...
 
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2FORCEFULL

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I'll be prop testing the honda powered coach I bought at cactus marine... the 250 hp honda is just a wound up 200hp honda with a program change... dought it has any where near the real power of a merc 250 v8... so not gonna be much gains to be had... first prop to try is gonna be a 14 1/8 x 15p 4 blade... If it can't pull that I'm gonna sell it and buy another one... what sucks about honda is the 250 is their biggest power,.. and when that's not enough... you have to rip every thing out and start over...the boat needs a 350 hp motor...
 

2FORCEFULL

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the other problem is the honda 2.0 gear, at very best, if I get it to 6300 max rpm... that's only 42 mph @ 6 % slip
 

2FORCEFULL

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if it was a 1.75 like merc.. i'd get to 48 mph with 6300 rmps..
 

HavaToon

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So here is my data from today moving up 2 holes to the highest setting with the cavitation plate even with the notch.

Verado 250 Pro, 1.85 gear and 14 P Enertia prop

Full load, double Bimini and 52 gallons
3000 rpm - 14mph - 34.87% slip
3500 rpm - 18 mph - 28.22% slip
4000 rpm - 23 mph - 19.75% slip
4500 rpm - 26 mph - 19.36% slip
5000 rpm - 28 mph - 21.84% slip
5500 rpm - 33 mph - 16.26% slip
6000 rpm - 37 mph - 13.93% slip
6470 rpm - 41 mph - 11.56 % slip

Full load, double Bimini and 30 gallons
5000 rpm - 30 mph - 16.26% slip
5500 rpm - 35 mph - 11.18% slip
6000 rpm - 39 mph - 9.28% slip
6480 rpm - 43 mph - 7.39% slip

The boat rode so much better almost like it was packing a little air. I attribute that to the drive no longer sucking the stern down. Turned better with the boat actually leaning in.

Now the bad, at neutral trim the prop has ventilation and if you have too much trim in hard turns it blows out as well. The boat still preferred slightly negative trim as it did on the middle setting.

My guess is I would really benefit from a 15 P 4 blade. Need to find a REV 4 15P to try.

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Lavey29

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Did you record any rpm/speed numbers before the modification to compare with? Trimming down in hard turns is normal for air entrapment type hulls.
 
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HavaToon

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Did you record any rpm/speed numbers before the modification to compare with? Trimming down in hard turns is normal for air entrapment type hulls.

I didn’t record numbers like this before. However my top speed didn’t change, it’s always been 42-45 depending on load. I feel like my RPM vs MPH is very similar before and after, basically even to +/- 1-2mph at most. What really impressed me was how the boat itself handled and rode, it was totally different and more reminded me of our Nordic deckboat. I think I just need a little more grip now and a 4 blade will give it to me.


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2FORCEFULL

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I'll be prop testing the honda powered coach I bought at cactus marine... the 250 hp honda is just a wound up 200hp honda with a program change... dought it has any where near the real power of a merc 250 v8... so not gonna be much gains to be had... first prop to try is gonna be a 14 1/8 x 15p 4 blade... If it can't pull that I'm gonna sell it and buy another one... what sucks about honda is the 250 is their biggest power,.. and when that's not enough... you have to rip every thing out and start over...the boat needs a 350 hp motor...
spent a couple days at havasu running the coach honda 250 power...real real happy with the results ...right where I wanted to be..
 

2FORCEFULL

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I got the 4blade 18p....it's a 15'' prop...the best prop so far for the Evinrude was the 14 1/4'' x 19p ,but still need 400 more rpms...1'' in pitch should get about 200 rpm...but the increase to 15'' diameter might take it back....but,... I can go up one more hole on the motor...and that might pick up the 400 rpms...testing this weekend...
 

2FORCEFULL

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spent a couple days at havasu running the coach honda 250 power...real real happy with the results ...right where I wanted to be..
???? got the honda running 45 mph at 5900 rpms in the heat.... with 60 gals fuel on board w/ bimin up...red line is 6300, probley see closer to that with cooler weather.... I put a honda 4 blade 14 1/4 x 17 p on, so I say she's pretty much there..
 

satellitemike

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I forgot where the Evinrude was at but I would assume you still like that one better than the Honda? Better low end and midrange?
 

2FORCEFULL

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I forgot where the Evinrude was at but I would assume you still like that one better than the Honda? Better low end and midrange?
the Evinrude is about 10 mph faster any given day, both toons have +'s and -,... but I just ventured into this toon deal....so learning what to look for...for me, I would say to any one... get as much power as you can... you can always drive a faster toon slower, but never drive a slower toon faster..being able to cruise around not on pin is key....the Evinrude loves 40 and will go 55, while the honda is at 35 and will go 45...toon boating..= big fun and comfort...and with a little power... sporty
 

warlock250

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2FORCEFULL

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SO IN COMPARIRISON , the 19 p and the 18p....the 19p goes 40 mph @ 4300 rpms/ 5% slip.. 12.3 gph ...the same 40 mph....but....the 18p is @ 4600 rpms 13.4 gals per hour, and 6% slip...so, to go 40 with the 18p it's 300 rpms and a GPH more...
 

satellitemike

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SO IN COMPARIRISON , the 19 p and the 18p....the 19p goes 40 mph @ 4300 rpms/ 5% slip.. 12.3 gph ...the same 40 mph....but....the 18p is @ 4600 rpms 13.4 gals per hour, and 6% slip...so, to go 40 with the 18p it's 300 rpms and a GPH more...
Can you get to max RPM's w the 19? If so sounds like a no brainer!
 

2FORCEFULL

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Can you get to max RPM's w the 19? If so sounds like a no brainer!
In the heat at the higher elevation of mead,and full load of fuel....no... but , the 19p cruises a faster speed using less fuel ...the fastest prop so far has been the 17p 3 blade that cactus put on the boat....but that was at havasu… running down river..so to make a fair comp, I'd need to run havasu again...when it cools down , it should work.... I can still go up one hole on the motor, and I think it'll help...if I go up one hole and it starts running the slip number up, I can go to the 18 p, as it is a bigger diameter, and has bigger blades..

the 19p ran 40 mph, @ 4300 rpms, 5% slip...not gonna get much better than that,....I need to try the 3 blade with the motor up, might see a better top end???? but pretty sure the slip numbers are gonna go way up @ cruise speed...

So you see.... fine tune is a lot of time and work for minimal gain, but as for the honda..going to a different prop..huge gain....


and again, the best prop for the honda was the honda brand 17p four blade
 

warlock250

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In the heat at the higher elevation of mead,and full load of fuel....no... but , the 19p cruises a faster speed using less fuel ...the fastest prop so far has been the 17p 3 blade that cactus put on the boat....but that was at havasu… running down river..so to make a fair comp, I'd need to run havasu again...when it cools down , it should work.... I can still go up one hole on the motor, and I think it'll help...if I go up one hole and it starts running the slip number up, I can go to the 18 p, as it is a bigger diameter, and has bigger blades..

the 19p ran 40 mph, @ 4300 rpms, 5% slip...not gonna get much better than that,....I need to try the 3 blade with the motor up, might see a better top end???? but pretty sure the slip numbers are gonna go way up @ cruise speed...

So you see.... fine tune is a lot of time and work for minimal gain, but as for the honda..going to a different prop..huge gain....


and again, the best prop for the honda was the honda brand 17p four blade
They like large diameter that's fo sho.

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throttle

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I am thinking of having prop tuned and labbed to get 2-300more rpm from it... I lost some top end speed this weekend in the heat and Sue's old boat passed me once, maybe twice.
 
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boatdoc55

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Well we have 7 hours on the boat now, Godfrey Sweetwater 2286(23'). I cruise it at 4K and get 30MPH and at WOT it is at 5K and 39 just touching 40 MPH. This is a lot more than I was expecting. Yamaha 150, 35 gallons of fuel and 4 large adults and all the boating crap that goes out for the day. 15 3/4x15 Saltwater Series Yami prop. I have a 15 3/4x13 on the way to get a little more RPM and as a spare or maybe everyday prop, who knows.
 

2FORCEFULL

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I am thinking of having prop tuned and labbed to get 2-300more rpm from it... I lost some top end speed this weekend in the heat and Sue's old boat passed me once, maybe twice.
that boat with a labbed secret weapon 29p prop did 92 gps….you'll need more motors to out run it...
 

2FORCEFULL

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Well we have 7 hours on the boat now, Godfrey Sweetwater 2286(23'). I cruise it at 4K and get 30MPH and at WOT it is at 5K and 39 just touching 40 MPH. This is a lot more than I was expecting. Yamaha 150, 35 gallons of fuel and 4 large adults and all the boating crap that goes out for the day. 15 3/4x15 Saltwater Series Yami prop. I have a 15 3/4x13 on the way to get a little more RPM and as a spare or maybe everyday prop, who knows.
all that for only 80k?, how much more was the trailer???? lol... just kidding.... lot of bang for the buck right there..
 

2FORCEFULL

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they sold that other toon I wanted, pretty sure I would have got it in to the sixtys on pin... oh well, having 3 toons is a little greedy....:D

but I did order a 3 axel trailer for sues toon...
 

boatdoc55

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they sold that other toon I wanted, pretty sure I would have got it in to the sixtys on pin... oh well, having 3 toons is a little greedy....:D

but I did order a 3 axel trailer for sues toon...
Ya, those heavy a$$ toons need a tri-axel!!! :D
 

boatdoc55

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all that for only 80k?, how much more was the trailer???? lol... just kidding.... lot of bang for the buck right there..
Steve, You know we paid just a tick under 46K out the door with the trailer. EVERYTHING included to go to the water. They even told me to bring it in any time I want to give it a once over to make sure every things OK DOKY. Yes, there are a couple of very minor things need looked at.
Couldn't ask for better guys than Cactus. Diana's boss just sold their older boat yesterday, guess where they're headed for their NEW toon?
 

2FORCEFULL

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Steve, You know we paid just a tick under 46K out the door with the trailer. EVERYTHING included to go to the water. They even told me to bring it in any time I want to give it a once over to make sure every things OK DOKY. Yes, there are a couple of very minor things need looked at.
Couldn't ask for better guys than Cactus. Diana's boss just sold their older boat yesterday, guess where they're headed for their NEW toon?
wow, hard to believe this was over 2 years ago...
 

fireman

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Hello, my name is Tom and I purchased a play craft pontoon boat ( Mercury 350mag Bravo3) and need some advice on prop selection.Im dealing with Hill Marine and I'm a bit confused. Can you plz call me (602 616-7728) I appreciate any suggestions you can offer thank you.
 
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