To flare or not to flare...

[yeller]

Hate to post yet another prop question, but I did a search and couldn't quite find what I was looking for.

I'm sending my prop back to Hydromotive in exchange for another. Question is, should I order the new one with or without the flare ring. I've been told the ring only helps for getting on plane and without, I could expect 3~4mph. Is this true for the 22C's

[cigarette30]

Yeller,

On the Cigarette I lost 1-2 mph, and found no differance getting on a plane. Are you having that much of a problem with the 22', that's the first time I have heard of it ........... maybe I missed an earlier post. Tabs and trim under, it's a rocket, with the 75 mph top end. With the "shorty" it just needed to be 'feathered" a bit.

[turbo2256]

Does your prop blow out loose grip running through waves? Do you then have to slow almost to no wake speed before hooking back up to take off to get back on plane? If so you probably need a ring. Properly sized it should cost you less than 1 MPH.

[yeller]

I'm having no problems with the current prop. Boat pops on plane quick and is a rocket from the start. It's just that I'm tickling the rev limiter now and I only have 6hrs experience with it. Once I get better and air the boat out more, I'll be in the limiter no problem. I'm returning the current prop for one size bigger. Current one has the flare ring and was wondering if I should order the new with or w/o.

[Pismo]

Yeller and Cig, what engines do you have in yor 22s? Shorty drives?, How short? and What props/pitch have you found best.

Thanks very much, considering a shorty after installing steering.

[ChromeGorilla]

If I recall, yellers boat is a 2004 496HO boat.

[yeller]

I never did send my prop back. I couldn't get a replacement before my holidays, so I kept it. I'm using a Hydromotive Q4. I'd like to try a couple of the new Turbos. Both the 3 and 4 blade. I'll have to see how much $ I have left after my holidays. :)

[BigGrizzly]

The flair only helps with prop exhaust. Next it does slow you down. The longer straight to helps direct the water flow. I have done a lot of testing with isentical props one with the flair and one with thw long tube.

[turbo2256]

The flair only helps with prop exhaust. Next it does slow you down. The longer straight to helps direct the water flow. I have done a lot of testing with isentical props one with the flair and one with thw long tube.


Never ran a boat with through the prop exhaust. My understanding from prop manufactures / designers and repair is that the ring redirects water flow across the blades and over the hub. Thusly the ring prevents prop blow out / cavitating. Only two of my boats ever experanced loss of grip the blow out ring ended it. Never did they speak of exhaust. I believe holes in the hub in some cases help exhaust through the prop.

[MOP]

The flare is past the flow to the blades, what it does is to create suction to help to pull the exhaust out of non transom exhaust engines. I feel any blow out benefit was due blade configuration not the flair, being a ring force is neutral in all directions.

Phil

[Walt. H.]

If you're running the drive trimmed up or have a shorter drive like I do the flare aka "defuser ring" will assist with stern lift because the top half of the hub is almost out of the water, which is counter productive when the usual goal is bow lift.
Because of that when I sent my prop to Julie @ Throttle-Up I had that ring machined off to achieve greater bow lift without having to over trim, and having the ring removed by itself should at best as advised by Julie and Matt see without the ring a gain of an additional 3/4 mph.

Note: That is not including the speed gain that the lab work and greater pitch will give.:crossfing

With that said the defuser ring does assist a heavy boat to get up on plane faster because of the stern lift qualities it gives and helps pull exh gases when the exhaust is routed thru the sterndrive, but this bottom end perf help is costing a little loss from your top end.
So if you don't need this low end assistance, you don't need a defuser ring.
Here's a pic of my current prop before and after having it labbed, pitch increased and the ring removed..

[LKSD]

For what it is worth, I personally dont care for the flare rings.. But thats me.. Jamie

[undertaker]

For what it is worth, I personally dont care for the flare rings.. But thats me.. Jamie


Well it aint worth NOTHING..what do you know about flare rings....:wink: :wink:


Undertaker:pimp:

...Sorry I just felt like bustin your balls......

[LKSD]

Well it aint worth NOTHING..what do you know about flare rings....:wink: :wink:
Undertaker:pimp:
...Sorry I just felt like bustin your balls......


Smart ass... :D :D J

[BigGrizzly]

MOP got it right. It doesn't direct the flow over the blades in any shape or form. I have heard so many stories from prop guys which is how I got into this. These tell you anything they don't the answer to. Kind of like Julie saying the Mplus 27 is called the widow maker. The flair is after the blades and has no directional force. The only reason it has any affect in surface peir4sing is because of the disturbance in thrust, which is definitely not needed.

[yeller]

Some say it doesn't help with getting on plane, others say it does. To add more fuel to the fire, I did a search on another site and stole the following:

Quote Brett of BBlades
...Our findings have been, remove the diffuser if blowout while planing is non existant. Difussers are more inportant with through prop exhaust. Risidual air can be drawn through the drive and cause some ventilation even with through transom exhaust.
...The diffuser may or may not help your planing.
...The diffuser may or may not affect your speed negatively.

Quote Matt of Throttle-UP
...If you don't have the flare ring installing one may eliminate the prop ventilation while getting on plane.

Quote Julie of Throttle-UP
...If you have a dificult time getting on plane then I would not recommend that you cut the ring off. This typically will make it more difficult to get on plane.

So my interpretation is the ring doesn't directly help a boat get on plane, but without it, some of the exhaust gases may (and I repeat may) exit around the front of the hub causing prop ventilation??

[RickSE]

My boat is not difficult to get on plane but I certainly can't just punch-it and I'm up on plane. I have to be careful and walk it up first before I really give it the gas or it'll blow out and cavitate the prop.

[BigGrizzly]

. This isn't fuel to the fire but a normal responceWhat it sounds like is no one will say which they don't know. First don't cut the ring off without extending the hub, it will suck air from open hole and ventilate the prop. Second no one wants to say weather it Will help speed just because some one will say " my friend John Smith did it and thats not true". I can do that too. All my testing and having identical props with a extended hub and defuser ring was not a wast of time. I know the answer. Did either of these people try this I bet not it would wast their dollar making time.

[Formula Jr]

You will see a gain in top speed if you do not have the flute in your prop.