posted 10-18-2006 08:34 PM ET (US)            

Ride in chop is alot improved, especially in the ocean. Slower planing speeds, excellent holeshot. She likes to run trimmed out on flat water. Acceleration at all levels is exceptional. My boat is heavily loaded with a big ol hardtop t-top and the thing feels like a sports car now.

Give it the gas and the boat really scoots.

I was running a 19 pitch Mirage Plus. It was ok. The 17 pitch Mirage Plus was terrible on my boat. The 17 pitch REV4 is fantastic. Runs the same top speed as the 19 pitch Mirage Plus, maybe a bit faster.

This is the first year I have not spent swapping props all summer.

4000 to 4800 rpms fuel economy is not great. Below 30 mph and above 40 mph this prop is awesome economy wise.

Have fun, it has made my boat a fun boat to run.

Rich

posted 10-18-2006 09:36 PM ET (US)            

Rich, how to WOT rpms on the 17" rev 4 compare to what you were getting with the 17" Mirage?

posted 10-18-2006 11:09 PM ET (US)            

The REV4 runs up to around 5600-5700 rpms. 5700 trimmed up pretty good and a light load. Sunday night under calm conditions, 2/3 fuel, one person and some fishing gear she went to 5600.

Based on my experience, a two inch difference in pitch when comparing the REV4 and the Mirage Plus will show a 200-300 rpm difference.

There is a noticable clunk when shifting with the REV4, but the Mirage Plus clunked pretty good too. They are both big and heavy propellers. There is an additional part for the FloTorqueII Mercury hub kit you should use for the REV4, that may help with the clunking a bit.

Rich

posted 10-19-2006 07:34 AM ET (US)            

One of the big bonuses that the Rev 4 props give me is docking control. The extra traction allows me to pivot the boat using just the motors. This was difficult to with any of the 3 blade propellers I've tried.

I think the Flo-Torque II hub system with the plastic sleeve causes the shifting clunk noises. The plastic is less forgiving to directional change than the traditional rubber hub.

posted 10-19-2006 03:01 PM ET (US)         

On "Whale Lure" I have found these results: (1.86 gears, 5800 redline)

Laser II 23" 60 MPH @ 5600rpm - props I have been running for 15 years

Laser II 21" 60 MPH @ 6000rpm - my spare set of props

(Laser II's are no longer recommended for offshore V-hull or cruising application)

Mirage Plus 21" 58 MPH at 5600 RPM (worst prop tried, but with very strong mid-range cruise - my HP-to-weight ratio not applicable to these props)

Revolution 4 19" 61.5 MPH @ 6350 RPM

Revolution 4 21" 62 MPH @ 5900-6000 RPM These are the props I bought and they are screamers.

The Mercury racing tech accompanying me on these trials indicated if I raised the engines another 2 bolt holes, I could run 23" Rev-4 and at 64 MPH. I decided against this, as I simply don't use this boat this way.

But I am going to raise my engines one more bolt hole, as Rev-4's like HEIGHT and can handle it without ventilation.
I am running the medium vent plugs.

As for the clunking, my gearcases handle the props OK, with very little "clunk", about the same as the Mirage Plus. On the newly designed Verado and Big Opti gearcases, there is none at all. From what I can tell, the older OMC V-6 gearcases which BRP inherited, including 2.6 & 3.0 liter sizes, don't handle them well at all, simply not being designed for such a heavy prop. Perhaps the BRP Rebel is better for those engines, being specifically designed for the 2.6-3.3 liter Evinrudes.

Merc Rev-4, Tempest Plus and Trophy Plus all come with the delrin drive sleeve filler, which gives the prop extra stability on the propshaft.

From my experiences on my relativley high power-to-weight V-hull, the twin Rev-4's gives incredible hull lift, so much that when running over 45 MPH, there is no sidespray off the hull, even as far back as the Whaler Logo, with the boat running on only the "V". This extra lift is where the higher top end comes from. Mid-range cruise is very strong and now super quiet, Verado like, which is amazing from conventional 2-stroke technology. Don't ask me why. Perhaps the long exhaust tube buries the sound better.

Running with a group of cruising Whalers this past Labor Day weekend, my first trip with these boats (a 19, 21, and 2-22's) since installing the Rev-4's, I realized how strong these prop really are. I found ourselves always way out in front, even though loafing along at 2800-3000 RPM (about 32-34 MPH). The ride of the hull is greatly improved with the increased lift, and you don't feel the additional cruising speed at all in spite of wave conditions. We were always having to stop and wait for the rest to catch up.

But of course, none of these other boats were running Mercs, either! I am the black sheep of the crowd.

posted 10-19-2006 07:18 PM ET (US)            

FYI, BRP isn't using those old OMC gearcases on its new products. They abandoned those in favor of the heavier duty Magnum gearcase and have been using those gearcases on V6 Fichts and E-TECs since 2002.

Pineapple -- Make sure you are running the right Flo-Torq II kit for your E-TECs with the prop nut end extended insert (BRP prop shaft is either longer or the thrust washer causes the shaft to stick out further from the propeller hub than is the case with Mercury. Also after you've run the props for the first time, retorque the prop nut because a fresh, new delrin sleeve seems to seat deeper into the hub after a load from use has been put on it for the first time. I found one of my Mirage props somewhat loose on the shaft after the sleeve seated into the hub and that caused some clunking sounds during shifting because the prop was moving on the shaft.

posted 10-19-2006 09:07 PM ET (US)            

That is why I made the comment. I did not intend to infer the bushing was designed specifically to reduce the "clunk".

When shifting into reverse to slow down when moving forward I do not experience the same extreme "clunk" as Bella con23.

The bushing for Mercury V6 applications

Jim- I don't see a forward bushing listed for the Evinrude on the Flo-Torq II application chart. It doen't sound like it would help you anyway.

Chart

Again I am sorry for the confusion.

Rich

posted 10-20-2006 12:33 AM ET (US)            

"...I am going to raise my engines one more bolt hole, as Rev-4's like HEIGHT and can handle it without ventilation."

posted 10-20-2006 07:34 AM ET (US)            

I was thinking about moving the engine up one hole and trying a 19 pitch REV4.

I can trim the engine up while running a heck of alot more with the REV4 than my Mirage Plus.

posted 10-20-2006 08:48 AM ET (US)            

List of hubs

posted 10-20-2006 10:04 AM ET (US)            

No, a 17" Revolution 4 will NOT act like a 19" prop from some other line. Do not drop down in pitch when switching to a Rev 4. I have demonstrated this on my own boat which generally runs 19" pitch props.

I have tried 19" Black Maxs, 19" Stiletto Advantage IIs, 19" Mirages, 19" Mirage Pluses and 21" Laser IIs. All of these props put the RPMs at the very top of my motors' recommended WOT RPM range.

I have tried both 17" Rev 4s and 17" Offshores (now Vensura) and both of these props allowed 400-500 more RPM putting my motors well over the red line and WOT.

I am currently looking for a pair of 19" Rev 4s which I hope will perform well.

posted 10-20-2006 10:13 AM ET (US)            

In reality, it will probably make no difference on any of our boats. I posed this question to Brett Andersen who used to work for Mercury in their propeller division and nows runs his own shop, BBlades.

Brett told me that the bushing was introduced when some high performance boats noticed their props developed a little wobble. It was determined the highly raked props like the Revolution 4 running in a surfacing application put too much stress on the standard hub kit so the bushing was developed to provide added support at the front of the hub.

posted 10-20-2006 11:26 AM ET (US)            

That is correct. It should also be noted that the bushing can be added to any Flo-Torq hub kit. It will do no harm; it is just a little piece of plastic.

I will also echo what Peter said about the importance of retightening the prop nut after running a newly installed prop. This should be done with ANY prop but especially so with the Flo-Torq hubs because it can take quite a bit of force to seat all the various parts together.

posted 10-20-2006 01:50 PM ET (US)         

On my old rib-side 21 "surf board", 19" is the prop pitch of choice for the 2.0 liter 150 Merc (1988). These results might be of interest to you: (2.0 gears, 5600 redline)

23" Laser II: 4800 RPM, 47 MPH
21" Laser II: 5300 RPM. 47.5 MPH (Best for cruising)
19" Laser II: 5700 RPM. 48 MPH (Best for overall use)

19" Offshore/Vensura 4 blade: 5500 RPM, 45 MPH
19" Black Max alum: 5500 RPM, 44 MPH

21" Rev-4 (borrowed from my 25): 4800 RPM, 47 MPH (same as 23" Laser II)

Clearly, to run a Rev-4 on this rig, I would need to drop down to a 17" Rev-4. In no other prop line, except perhaps a Mirage Plus, would this be necessary) The engine's gearcase clearly did not like this prop! And the hull does not need this much stern lift.

posted 10-20-2006 06:06 PM ET (US)            

I happened upon this info when trying to figure out how to reduce the loud clunking on my Troph Plus equipped Mercury 115efi 4-stroke. Tom Clark recommended I switch to the Flo-Torque III hub which I am definitely going to try (thanks Tom). This leaves me with the question - what application was the Flo-Torque IV designed for? I cannot find any reference to it on the Merc site but did find one online prop store which sells it. I wonder if the Flo-Torque IV was designed for the larger gearcases running heavy ss props? I find it odd that Merc would release both the Flo-Torque III and IV versions but then make no reference to them in the prop section of their website.

posted 10-20-2006 09:33 PM ET (US)            

You would just need the Evinrude hub kit.

It does sound as though a 15 pitch is what you need. Strange though, since you were running the 19 pitch on the other motor.

posted 10-21-2006 02:18 PM ET (US)            

If you would- contact me with your address again. Use rtkenny@comcast.net.

Rich

posted 10-21-2006 08:57 PM ET (US)            

When I installed the Rev-4, top speed increased to 41.5 knots at 5,500 RPM, cruise increased to 26.5 knots at 3,750 RPM and I got about 3.1~3.2 nmpg. Great acceleration and excellent low speed planing at 8~9 knots with the engine and tabs all the way down.

In 2004, I was looking for a Mirage Plus 17", but could only find a Mirage Plus 19". Top speed again increased to 43.0 knots at 5,200 RPM, cruise increased to 29.3 knots at 3,750 and about 3.2 nmpg. Acceleration was OK and low speed planing increased to about 9~10 knots.

So, I'm running the Mirage Plus 19". I like the economy and higher cruising speed. Two summers ago we cruised over to Glacier Bay National Park & Preserve with a full load, two people, extra, fuel, water, food, and camping gear using the Mirage Plus 19". Ran at 3,900 RPMs to get the 29 knot cruise and made the 138 nm round trip using 46 gallons.

posted 10-24-2006 10:12 PM ET (US)            

I removed the REV4 and installed my Mirage Plus this past weekend. After the installation I ran the boat for a half hour and returned to the slip. I was able to turn the prop nut a good 1/4 turn more after running the boat.

A comment on the way the Delrin sleeve fits into the propeller. I noticed after changing propellers a few times that initially with a new sleeve and/or a new propeller that the sleeve will not slide all the way down into the propeller, as previously stated.

I started seating the sleeve with a hammer and a flat object (lightly, and a spare thrust washer) to seat it as far down as it will go into the propeller. This way I was not depending on the tightening of the propeller nut to seat the sleeve all the way up into the propeller.

The infamous CLUNK was as evident with the Mirage Plus as it was with the REV4. Same Flo-TorqII hub kit and I did use the additional bushing, why not. The Mirage Plus is no lightweight either.

Rich

posted 11-05-2006 01:50 AM ET (US)            

WOT: 40.5 mph at 5000 rpm
Conditions: very light chop (<1'), rolling 4-6 foot swell, light wind, 77 gallons of fuel, just me aboard.

Although this prop has a bit too much pitch, it really holds like glue. In that respect, it feels a lot like the 19" High Five I was running on the old motor. Holeshot was not as good as I expected, I suspect because the prop has such low slip the motor takes a second or two to really rev up. The prop has the vents plugged completely, and perhaps with them unplugged holeshot would be better. The 17" Mirage Plus actually seemed to have better holeshot, which is not what I would have expected. Once the boat was up on step, it was going 30 mph in no time. Mid range acceleration was awesome.

Other impressions:

Even with the motor trimmed way out, the bow seemed lower than with other props. Does this prop have a tendency to lift the stern of the boat?

The thunk was pretty noticeable. Running the boat out in open water it didn't bother me too much, but putting it into the slip, when I shift in and out of gear several times as I maneuver, it was really annoying. I can't help but wonder what this is doing to the lower unit over time. I'm using a Flow-Torq II hub kit, with the prop nut tightened to 80 ft-lbs.

With the motor trimmed all the way in, steering to port was very stiff. This went away as soon as I trimmed out a bit. I am guessing that the trim tab is biting with the motor tucked in, and it needs to be adjusted. Does this make sense?

The boat stayed on plane at a lower speed than with the Mirage, down to about 15 mph.

The prop tolerated much more trim out, and did not ventilate easily like the Mirage Plus. The motor is mounted fairly high (3rd hole from top) and this prop seems to run well in that position.

Conclusions:

posted 11-05-2006 01:50 PM ET (US)            

Your experience with the Rev 4 is consistent with my own.

Yes, the Rev 4 is a stern lifting prop and it is remarkable how a boat will seem to ride higher in the water. Though the diameter is this prop is relatively small, it still has large blades, they are just swept back so far. This is part of why it is such a clunker; it is a lot of stainless steel. The Rev 4s are the heaviest prop I have yet weighed for V-6 outboards.

It is also remarkable how well the Rev 4 grips. I could almost not get them to ventilate at all on my boat no matter how hard I turned or how the motors were trimmed.

The ability to hold the boat on plane at slower speeds is another characteristic of this prop and one which is of value to those who run their boats in choppy water. I suspect if you tried a 15" Rev 4 you might even be able to hold your boat on plane at even slower speeds.

I agree that 5000 RPM is not enough and you should reduce pitch. 15" Rev 4s are hard to find on the used market.

I do not have any personal experience with the Stiletto Bay Pros but I have sold two of them to guys who were very pleased with them. It might be worth a try. I can get you any Bay Pro for $300, delivered.

posted 11-05-2006 02:27 PM ET (US)            

The Bay Pro appears to be a similar design to the Offshore, and for the price it is very tempting. The question again is what pitch: 15" or 17"? The 19" Offshore did not let the motor rev over 5100 rpm, so that indicates that the 17" would be just about right in that prop. Is it fair to guess that the Bay Pro will perform more like the Offshore or more like the Rev 4? Do you know what boat/motor combos those 2 Bay Pros went on?

If I could find another High Five with a Flow Torq hub, I'd love to try that on this motor as well. I really liked the way that prop ran on the old motor, and haven't ruled out getting my old High Five re-hubbed sometime down the road.

Any thoughts on the really stiff steering with the motor trimmed in?

posted 11-05-2006 02:48 PM ET (US)            

Yes, The trim tab needs to be adjusted on your motor. Move the trailing edge of the tab to starboard.

Yes, it comes down to finding the best prop for your boat and your type of boating and not about saving a buck or two and not necessailry about which prop produces the highest top speed.

The challenge to is be able to experiment with all the possibilities. I have tried 15 different propellers on my own boat and am still looking for several more including a 19" High Five, a pair of 19" Rev 4s, a pair of 19" Tempest Pluses, a pair of 19" Enertias and the Bay Pros.

posted 11-06-2006 10:50 PM ET (US)            

How high can I raise my cav plate above the lowest part of my hull? Presently it is around an inch or 2..

How many flow torks are there and what are the differences?