2016 Tahoe 215 Xi Deck Boat - Switching from Aluminum to Stainless

jwdavis28

Seaman
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Mar 14, 2016
Messages
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Anybody out there already made this switch? I just prefer a stainless prop over aluminum. Picking up this new boat on Saturday and it comes with a "factory matched" aluminum prop. Can't find the specs on it. Boat has the Mercruiser 4.5L 250hp motor.

What are you using and what are the plus/minus?

(think I just found the stock aluminum prop specs 151/4x18)

Thanks!
 
Last edited:

blamtro

Petty Officer 2nd Class
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Jun 14, 2011
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145
Stainless props look a lot nicer then aluminum. However, aluminum props are much cheaper and offer a sacraficial benefit it that if you hit anything under water the aluminum will get damaged much faster. Stainless you run a higher risk of ruining the drive internal componets and gears.
 

jwdavis28

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Mar 14, 2016
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I appreciate the input blamtro. I've owned boats for 30 years and really prefer the stainless over the aluminum. Yeah I know the the risks associated with prop strike and lower unit damage but that's a risk I'm willing to take. Don't know if it's just perception or reality but I've always felt that my boats performed better with the stainless props when doing the main things I do....cruising and tubing/skiing.

Just looking for anybody that has made this switch.
 

Texasmark

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Dec 20, 2005
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Stock alum is usually not cupped, usually no rake, and thick blades due to the alum. SS props usually have cupping, always thin blades, may have rake which you don't need, and porting which you don't need....with an I/O so say the experts. Expect the SS prop to pull your rpms down slightly and increase your top speed given everything else the same. If you are lugging at your WOT as it is, drop down to the next available lower pitch SS. If you are ok then get the same pitch. If over the upper recommended rpm go up to the next higher pitch.
 

jwdavis28

Seaman
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Mar 14, 2016
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Thanks for the input gentleman! Any feedback on 3 vs 4 or 5 blades on this application?
 

jwdavis28

Seaman
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Mar 14, 2016
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Well with a lack of response I can only assume that it's up to me! I will do some research and when I begin testing props will post the info for others to consider if they are looking at a similar swap.
 

Scott06

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Apr 20, 2014
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You didn't list what your current WOT rpm and speed or the performance issue you want to solve or improve so it's hard to respond or make a recommendation. I have switched two boats fom 3 to 4 blades and gotten better holeshot, planning at a slower speed, better watersports towing, while loosing a mph top end. If that's where you intend to use the boat I'd recommend a 4 blades. Say if you have 19" 3 blade try a 18" four blade. Best bet find a prop shop who will let you try them.
 

jwdavis28

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Mar 14, 2016
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Scott06. I'm still working on the current WOT as I'm still in the break in period and can't hold it WOT much yet. Lower planing speed and watersports towing is what I will be doing mostly. Top end is nice but let's face it...a deck boat isn't going to be WOT much anyway. Sounds like 4 blades might be the way to go.
 

Scott06

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based on that I'd say a four blade is what you want. Maybe not as sexy as other options but the Michigan vortex worked nice for me, and is aluminum so was a great value.
 

jwdavis28

Seaman
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Mar 14, 2016
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I will get WOT RPM's today. I will have a full fuel tank and 6 people but we shall see. If I'm hitting towards the top of the 5200 max then i'm thinking 4 blade of the same pitch. Have to see. Stay tuned as I will want feedback!
 

jwdavis28

Seaman
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Mar 14, 2016
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Ok. 1/2 tank of fuel. 3 people. 85 degrees. Light chop.

Turned 5375-5400rpms. That's actually 200 RPM's over the recommended top end. Didn't hit the rev limiter that I could feel.

So it appears that I'm a little under propped?
 

Sea Rider

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Sep 20, 2008
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Over revving + 200 rpm at wot is nothing, will going for next more pitch lower wot revs to 5200 and make the trick, who knows. Personally would stay with current prop if boating with max 3 boaters.

Happy Boating
 

jwdavis28

Seaman
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Mar 14, 2016
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I would like more holeshot and corner holding in the midrange for cruising and water sports.
 

Sea Rider

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Sep 20, 2008
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Same 18 pitch on a 4 blade prop should give less wot revs as current 3 blade 18 pitch, need to go for a 17 pitch to achieve same theoretical wot revs..

Happy boating
 

youmansjason

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Joined
Jun 3, 2005
Messages
68
The concern about a Stainless Steel prop causing more damage to your prop shaft/gears if you hit something with it is really no longer an issue if you get a SS prop with the break-away hub. For a Mercruiser, it's called Flo-Torq II. These are a specially designed hub that you buy as a kit and insert into the SS prop, and it's designed to take the impact if you hit something with the SS prop. I highly recommend it.
 
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