Moderated Discussion Areas
  ContinuousWave: Post-Classic Whalers
  Highfive Propeller for Dauntless 18

Post New Topic  Post Reply
search | FAQ | profile | register | author help

Author Topic:   Highfive Propeller for Dauntless 18
bravocharlie posted 07-19-2005 08:44 PM ET (US)   Profile for bravocharlie   Send Email to bravocharlie  
I've done a search for propellers and read several good threads that touch on the subject.

My situation is this:

I have a 135hp Optimax with a 3 blade MiragePlus 17P. I want to buy a spare propeller to have onboard. Rather than duplicate the MiragePlus, I went to Mercury Marine's website and used their lame propeller selector.

I then called two different propeller suppliers and got the same recommendation from both: Highfive 13.5 x 17.

From what I've read and what I've been told, it appears as though I should stick with the same pitch as is currently on the motor (17P). At 3500 rpm, I run at 25 mph and WOT at 5500 rpm and 40+/-. Is this correct?

Also, from what I've read and been told, the out of the hole performance should be stellar with the 5 blade, it should be smoother (I do have low speed vibration with the 3 blade MiragePlus) and there shouldn't be too much, if any sacrificed on the top end. Is this correct?

I've read several posts here regarding selecting the correct propeller for the motor: i.e. not being able to achieve maximum rpm or have a prop with a size and/or pitch that put too much of a load on the engine. If I go with the 13.5 x 17 Highfive, will this be the case? I've been told not.

Finally, I run in some rough choppy water for a 18 foot boat. Keeping the boat on plane at 3000 rpm trimmed in is sometimes difficult. From what I've read and been told, the Highfive should help with this problem in rough water.

Thanks in advance.

Whalerider posted 07-19-2005 10:04 PM ET (US)     Profile for Whalerider  Send Email to Whalerider     
From what I have read, most people are very disappointed in the High-Five. You are right that you will have a great hole shot, but every other parameter suffers especially the top end. Now, if you are a hard-core water skier you might be happy...that’s what it is for, slow and steady. Try a four blade for smoother running without loosing too much near the top.
bravocharlie posted 07-19-2005 10:19 PM ET (US)     Profile for bravocharlie  Send Email to bravocharlie     
If I went with a four blade prop, I am assuming that I should go with the Vensura (offshore series)???

Need a great four-blade propeller? The Mercury four-blade, stainless steel Vensura props deliver. Better acceleration, aggressive holding offers great performance with light weight 18' - 24' center consoles, ski boats or runabouts. When a three-blade just won't cut it, this prop is what you need.

For single 135 - 175 hp outboards - aluminum multispecies fishing boats
For 3.0L - 5.7L Alpha sterndrive runabouts
For V-6 outboard or 3.0L - 5.7L Alpha water ski boats
For twin offshore 135 - 175 hp outboards
R/H and L/H rotation (17" - 23" pitch)
Equipped with Flo-Torq II hub system

Whalerider posted 07-19-2005 10:34 PM ET (US)     Profile for Whalerider  Send Email to Whalerider     
Sounds better to me.... I run a Power Tech UN200OFS4R17P on my 150 Opti and I am happy with it. I replaced a Mirage 17p.


bigjohn1 posted 07-20-2005 08:13 AM ET (US)     Profile for bigjohn1  Send Email to bigjohn1     
If the High Five is really what you want, double check the pitch sizes currently available. When I was considering one, I saw on the Merc site that it was made as low as 17 pitch. Then I went to both my dealer AND various online prop sources...the lowest High Five I could find was 20 pitch. This info might have changed recently but I believe Merc's intent is to supply them down to 17P in the near future but I think currently, they are unavailable in pitch sizes below 20.
bravocharlie posted 07-20-2005 08:49 AM ET (US)     Profile for bravocharlie  Send Email to bravocharlie     
17P is available in the HighFive.
bkloss posted 07-20-2005 09:25 AM ET (US)     Profile for bkloss  Send Email to bkloss     
"Finally, I run in some rough choppy water for a 18 foot boat. Keeping the boat on plane at 3000 rpm trimmed in is sometimes difficult. From what I've read and been told, the Highfive should help with this problem in rough water."

I have the same setup and run in rough seas as well. You might consider raising your motor up 1 or 2 holes as it really makes a huge difference in the boat and motor performance under those conditions. My motor was delivered mounted all the way down and I raised it 2 holes.

bsmotril posted 07-20-2005 09:32 AM ET (US)     Profile for bsmotril  Send Email to bsmotril     
I tried a 17" High five on a boat I had that was originally propped with one of the old Mirage's, also in 17". the high five behaved like it had 2-4 inches less pitch than the Mirage. IE, RPMs were about 3-400 rpms higher at any given speed across the board. If it were me, I'd go up 2 inches in pitch on the high five as a starting point. BillS
Marlin posted 07-20-2005 09:52 AM ET (US)     Profile for Marlin  Send Email to Marlin     
bigjohn, the High Five starts at 20" pitch (and up in even numbers) in the midrange gearcase size, which I believe is up to the 115 HP engines. For the larger engines it's in odd numbers.
bravocharlie posted 07-20-2005 11:58 AM ET (US)     Profile for bravocharlie  Send Email to bravocharlie     
I'm backing away from the Highfive and focusing on the four blade Vensura as described above.

This morning, I tested the WOT RPM value of the existing MiragePlus 17P which resulted in 5500 rpm and 41 mph.

So, I can conclude that the 17 is the proper pitch for the boat right?

Now, Mercury suggested that I go down one pitch to a 16 if I go to the four blade.

Does anyone have any experience with the four blade?

bigjohn1 posted 07-20-2005 06:06 PM ET (US)     Profile for bigjohn1  Send Email to bigjohn1     
Marlin, thanks for the info..I did not realize that.
dgp posted 07-20-2005 07:43 PM ET (US)     Profile for dgp  Send Email to dgp     
...Mercury Marine's website and used their lame propeller selector.

Please explain why the prop selector is lame.
prm1177 posted 07-25-2005 12:53 PM ET (US)     Profile for prm1177  Send Email to prm1177     
The prop selector on the Mercury site always recommends a pitch that is way too high. For my twin Opti 135/Conquest it recommends a 23 pitch. I currently run 17 pitch which places me in the right RPM range. Running a 23, would place me way out of the theoretical range.
Whalerider posted 07-25-2005 03:55 PM ET (US)     Profile for Whalerider  Send Email to Whalerider     
I ran the Merc prop selector for my Nantucket. I used the weight instead of the total length choice. One of the props it selected was a Mirage 17. I ran a Mirage 17 on my Nantucket at one time and the numbers were fairly close. I also ran it for my Action Craft and it was right on. For fun, I ran the numbers on a Conquest 235 w/twin 135's and came up with 19 to 21 inch props, not 23. Seems that you must to select the correct hull type and use the TOTAL weight, not the length for BW style boats, and then it’s fairly close.


bravocharlie posted 07-28-2005 10:29 PM ET (US)     Profile for bravocharlie  Send Email to bravocharlie     
Follow up:

After extensive research, calls to Mercruiser and Whaler along with the help of some others on the forum, I have ordered a 17P Vensura Four Blade.

Upon its arrival, I will report my findings.

Thanks to everyone who provided assistance.

bigjohn1 posted 07-28-2005 11:05 PM ET (US)     Profile for bigjohn1  Send Email to bigjohn1     
I'll second what dgp states about Merc's prop calculator. Maybe its spot-on for some boat and engine combinations but not all. Unless I am using it incorrectly, it seems to recommend way too much pitch. I said the heck with it and took recommendations obtained here on the forum - I have not been dissapointed and my engine is operating in the correct rpm range.
bravocharlie posted 07-31-2005 05:56 PM ET (US)     Profile for bravocharlie  Send Email to bravocharlie     
Well, I put the new 17P Vensura on the 135 Opti today to see what would happen.

Preliminary results are as follows:

Loss is Speed from mid range to high end: 2-3 mph

Out of the hole: Nearly instantaneous...a significant improvement over the 3 blade Mirage Plus

Vibration: In gear, idle, the prop produces a low frequency vibration...(is this normal?) At 800 rpm, it smoothes out and vibration is gone. I noted some mid range vibration, but wasn't sure what it was exactly. I thought the four blade was supposed to be smoother than the 3 blade? Do you think if I removed the prop and reseated it on the shaft by rotation it a few splines it would make any difference?

Handling: no more skidding sharp turns. The prop really holds the turns much better.

Mid range acceleration: the boat just launches when fuel is added to the fire.

Top End Speed: Looks like 3 mph drop.

Wide Open Throttle: 3 blade MiragePlus: 5500 rpm
Wide Open Throttle: 4 blade Vensura: 5600+ to overspeed alarm. Not sure why this is; perhaps test w/ 3 blade was flawed.

Rough Water Performanc: This is the one area that REALLY suprised me. The boat holds the water much better with the four blade. Now, can someone explain why this is?

Whalerider posted 07-31-2005 07:05 PM ET (US)     Profile for Whalerider  Send Email to Whalerider     
Its performance nearly as my Power Tech's. Actually Power Tech's is a clone of your Vensura, so I would expect similar data. I am told that the reason for the better holding is...more blades in the water while in the rough stuff. Sounds like you could use another inch of pitch in your new prop. If it was mine I would have a prop shop increase the pitch slightly, you will gain back almost all of your WOT speed loss, midrange speed should be better than the Mirage and you will stay off the overspeed limiter. As for the vibration...I should be smoother. If 2 props have had the same/similar vibration, then I would look somewhere else, but I don’t know where, maybe some here can help.


p.s. I had a really good prop guy tell me that the Mirage props he has seen have significantly more pitch than advertised.

Post New Topic  Post Reply
Hop to:

Contact Us | RETURN to ContinuousWave Top Page

Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.