Spitfire Prop

kaydano

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Anyone tried a spitfire yet? I would be very curious what you think.
 

Bamaman

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For an aluminum prop, the Spitfire is probably as good as you can get. I read on Mercury's website about it.

If you were going toward a stainless steel propeller, the Enertia by Mercury is available in 1" pitch increments, and it's really good for a pontoon.

I used to go through am aluminum propeller a year on my inboard outboard boats. When I switched over to a stainless steel prop, I went 10 years without any problems. They're worth the investment to me.
 

kaydano

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I guess I figured my motor wasn't big enough to warrant a SS prop. Might be wrong, but that's what I've been thinking.
 

kaydano

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Ha ha ha. Can't let me forget I should have gotten that 150, can you? I know, I know, I was warned by just about everyone on here almost 2 years ago, and I still can't get away from it. I admit, I'm the one that keeps bringing it up though.

Live and learn. Or, if you're reading this and on the fence between the 115 and 150, read and learn. Much less painful.
 

lakeliving

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We bought the biggest we could get for the 22 sslx (115hp) That way we had no room for bigger motor without going to a bigger boat
 

Ben & Suzy

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The Spitfire should be a good prop. Much like the Solas Amita4. Your current Black Max is performing VERY well as far as top speed is concerned. It's doubtful that a Spitfire would exceed that number. Where it should excel is in hole shot and midrange performance. It should have better load carrying characteristics without losing too many rpm's in the process. A great prop for pulling tubes. This has been my experience with the Solas Amita4.

When you have a prop that's performing as well as your current Black Max, don't expect the miracle numbers that you read on the Internet. The Spitfire claims of a 5-7mph increase in top speed ain't gonna happen.
 
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kaydano

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I think you are spot on. My assumption has been I will lose some top speed. I am hoping to gain in the area of pulling a tube with a full boat though. Plus I feel I should have a spare on board.

What I am really looking for is someone that has one, to get some real world input so I can hopefully pick the right size the first time. wondering if I should get the size I have or step up one pitch.
 
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Ben & Suzy

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Mercury has a Dealer Prop Demo Program. If I read things correctly and you can find a supporting dealer, it appears that you can demo a prop for $25. Not a bad deal if you choose the incorrect pitch or the prop doesn't perform as expected.

I plan on testing a Spitfire on my brother's Benny 2050RL tritoon with a Yamaha F115. RIght now it's pretty consistant at 33-34 mph with a best of 35 mph.

The downfall of the 115's compared to the 150's is, of course, horsepower / torque.........but just as important is prop diameter. A 14" diameter prop is the largest offering for the smaller gearcase of the 115's. A tritoon / 115hp combo is generally in the 15p range. As with most midrange props, the diameter tends to decrease with pitch increase, thus losing blade area.....or pushing power for lack of a better term. Diameter is key for the overall performance of a load carrying boat. I run a 16" x 3 blade on our Benny with a 150 most of the time. After buying / testing many props since we bought our tritoon, I've finally sold most of my prop collection (all stainless steel) to our local dealer. I did keep 3 or 4 for tweeking though. I'm never satisfied lol!

I've been playing with props for 35 years, both racing and recreational. Testing is the only true way to know what works. The rest is guesswork.
 
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kaydano

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Thanks - Didn't know about the prop demo program. You posted lots of good info. I understand pitch, but hadn't figured out how diameter worked into the equation yet. I get the increase in surface area an increased diameter gets you, but how that intertwines with pitch and the impact it has on reducing engine rpm has me stumped. I guess the fourth blade is how they get more surface area without increasing diameter. It's like balancing a three legged chair. Only worse. I mean I get the basics of it, just can't seem to find much info on how to optimize the three pieces for a specific boat. Probably never will. Wrench and test, I guess.

Let me know how your brother's boat turns out with the Spitfire. Very curious.
 
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Ben & Suzy

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There is so much more than just pitch and diameter that enters into the equation. Blade area, pitch progression, blade shape, rake, cup / roll and where it's placed on the blade, barrel / hub length all factor into how well a prop performs on a particular hull.

Yeah.......it's confusing lol!
 
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kaydano

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I can see where those things (rake, cup, etc) would factor into decisions between opposing brands/models, and I'm sure you've dealt with all this having had a "collection" (gee, I only have one). Fortunately I don't have to deal with all that since I've decided on the Spitfire. Don't go talking me into a different prop model or my head will explode!

Quick question, is there any way to know what hub I have, short of taking the prop off the boat? (Flow-torq II, Flow-torq III, etc.) I will have the boat back at the house in a week or two, and plan to remove it to look, but if there's a way to tell without taking it off, one less thing on my list.
 

Ben & Suzy

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The Flo-torq ll is the standard hub kit that typically comes with an aluminum prop. If you should happen to experience any gearcase rattle, which is unlikely with aluminum and more common with heavy SS props, you can always upgrade to the FT lll or lV. Save your money for now and just swap hubs. You should be just fine.

BTW, my best performing prop is / was a custom 4 blade. Now if I can find a nice used Rev4 to have cut on, maybe it will come close to the custom one. The quest never ends lol!

Yes, I like a good 4 blade. I like em..........I like em a lot!!
 
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kaydano

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My main reason for getting the Spitfire is to have a spare prop on board. And, if I'm going to do that, I might as well get a prop that will make my current prop the spare prop, if you know what I mean.

Anyway, getting a second hub kit would be for the same reason (in case the breakaway breaks away). So, that's why I was curious what I had now, as I'm thinking I'd just get the same kit as a backup (so parts would be interchangable too, not just a whole hub change out). Unless I'm missing something here, please let me know. I'll take the prop off when I get the boat back to the house to see what it is for sure. Good to know it's likely a Flo-torq II though.

Thanks!
 

cwag911

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All the Merc props I've bought came with a new flo-torq II in the box. I use a flo-torq III so the prop doesn't rattle at idle. You won't have that problem with aluminum.
 
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melissanorwood1

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Mercury has a Dealer Prop Demo Program. If I read things correctly and you can find a supporting dealer, it appears that you can demo a prop for $25. Not a bad deal if you choose the incorrect pitch or the prop doesn't perform as expected.

I plan on testing a Spitfire on my brother's Benny 2050RL tritoon with a Yamaha F115. RIght now it's pretty consistant at 33-34 mph with a best of 35 mph.

The downfall of the 115's compared to the 150's is, of course, horsepower / torque.........but just as important is prop diameter. A 14" diameter prop is the largest offering for the smaller gearcase of the 115's. A tritoon / 115hp combo is generally in the 15p range. As with most midrange props, the diameter tends to decrease with pitch increase, thus losing blade area.....or pushing power for lack of a better term. Diameter is key for the overall performance of a load carrying boat. I run a 16" x 3 blade on our Benny with a 150 most of the time. After buying / testing many props since we bought our tritoon, I've finally sold most of my prop collection (all stainless steel) to our local dealer. I did keep 3 or 4 for tweeking though. I'm never satisfied lol!

I've been playing with props for 35 years, both racing and recreational. Testing is the only true way to know what works. The rest is guesswork.
We have a 2250GL Bennington we have to buy a new prop for it. Its a 2007 Mercury 115hp. Maybe you can enlighten me on what you think. Its a 15p. Should I go with a smaller pitch for smoother operation.. A 4 blade stainless steel or 3 blade? Whats your thoughts?
 

2fast4u

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We have a 2250GL Bennington we have to buy a new prop for it. Its a 2007 Mercury 115hp. Maybe you can enlighten me on what you think. Its a 15p. Should I go with a smaller pitch for smoother operation.. A 4 blade stainless steel or 3 blade? Whats your thoughts?
On my 2250GL i have two alu .props a solas 13.5 X 15 yields 28.3 mph @ 5600 rpms my second prop is a merc 13.5 X 13 yields 29.4 mph @ 6000 rpms both are 3 blades . I think the extra cost for a
Stainless prop is not worth the money on these 115 hp motors, I use the 15p most of the time, I only carry two or three adults most of the time. If i loaded the boat with more people the 13P works better. Hope this helps you .How does you boat om top speed? My boat is a 2 toon no lifting strakes
 
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