Help what Prop
 

Hello,

my name is Thorsten, and I come from Germany.

I've read already a lot in our forum and now I've some questions.

My boot is a Stingray 230sx with a 350Mag engine 300Hp.

Which propeller you can recommend me for a good speed and acceleration?

In Germany Stingrays are rare and nobody can give me a good tip.

Thank you beforehand.

Greet Thorsten

With that engine, from what I've read from other 230 owners, most likely a 23" Mirage. Bravo or Alpha drive? I've also read where the Bravo 1 prop works very well, better control.

It is an alpha. in moment I have a 22 revolutions 4 Blade prop with him I reach only 4200 rpm. 23 is not too big? the engine can turn 5200 rpm.

I would try a Laser II. That is what stingray recomends. I simply think that the Mirage is too big and slow for that boat, with the deep drive. The one I rode in, used a 25 Laser II, had a 496HO and topped 70 mph @ 4900 rpms ca. It had 1.5 gears. The owner tried a mirage+, and it just slowed the entire thing down to about 68 mph,

Brett, any thoughts?

Hi Thor...
Welcome to OSO...I had a 24x7 Condor with a 300 hp 350 spinning a 21 Laser II through a 1.5 Alpha and could run 62+/-all day without an issue. Don't let your RPM's go beyond what Mercury recommends.
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I have tried 21 lasers. With it the boat comes very slowly from the water. What do hold you from 21 Mirage? To many thanks to for yours help.

The reason why the boat is slow out of the hole, is that the 21 is too tall. Try a LaserII 19", it also has a larger dia. than the 21. Your boat should run right around 55-56 mph. You will never run a 23 @ 5200 with 8-10% of slip. You haven't told us how fast you are going @ 4200. About 52-53 mph? If you ran a 23 @ 5200 you would see 69-71 ish mph. My point is, the mirage is a large and heavy prop for the power and boat you have. If the Laser 19 does not work, you could try the enertia in either 19 or 20. It has a bit more bite than the Laser, but not as much as the mirage. The 19" LaserII, Enertia 19" and 20" are all 14" dia. If you want to go four blade. Try a Vensura 19" or Revolution 4 in a 17". Aim for 5000-5100 rpm.

I run a 21" Laser II on my 22' boat, which only has a 5.0 MPI 260 HP. The Rev 4 is a beast of a prop. I know a few Stingray 230 owners with that size power that are running either the Laser II 23" or the Mirage. I'll check back again to confirm.

It also depends on the boat.
 

[QUOTE=VtSteve;3152354]I run a 21" Laser II on my 22' boat, which only has a 5.0 MPI 260 HP.

What kind of gears are you running with your 5.0 mpi? What kind of speed?

With 4200 I drive about 55 mph with 21 lasers. With 22 revolutions with 4100 about 53 mph.

[QUOTE=A.O. Razor;3152407]I have the Alpha One 1.62 gears. Top speed this year so far is 55 mph gps, but it's been lagging lately. I personally think I did better with the 21" Black Max Aluminum, higher rpms and a top end of 57 mph. Less pulling power though.

I'm thinking of trying a 21" Vengeance, which is pretty close to a SS version of the Black Max.

Those can't be accurate tach readings, or you'd be hurting (lugging) your engine. I can spin my 21" Laser at 4900 rpms with my 5.0 engine.

The Rev 4 prop is a beast, and lots of power needed. Rarely does a boat not lose at lease 5 mph with that prop. Immense pulling power though.

A Hi-Five might be a good all-around choice.

Are your speed measured on gps or pitot speedo? 55 mph @ 4200 with the Laser 21" gives you a slip of 1 % with a 1.5 gear. I think the alpha is 1.47 not 1.5, but i could be wrong. That would give the Laser 21" a slip of 3 %, and thas is REALLY low. Your Revolution 4 has a slip of 8 or 9 %. IF the Laser has that low a slip, you don't need a bigger prop. Then you could see 60 with a 19" Laser. No matter what, the Mirage+ will be slower. If you measured the speed with a pitot speedo, then you could be @ 52 or 53 mph 5 or 7 % slip with the Laser, witch seems a bit more realistic. Then a 19" should give you about 57-58 mph. @ 5100 rpm's and the Enertia 20" would be @ 60-61 mph. As far as I remember, 5100 rpm's is where the 350 mag have most power for top speed.

My suggestion would be, to have a Revolution 4 17" for skiing and fun, and either a 19" Laser or, 19" or 20" Enertia for cruising/top end. Do you have a shop near you, that have some test props?

+1 on the hi-five. Nice for skiing and fun.

The reason for the higher rpm's with the alu prop, is that the blades flex, and then you get the rpm's up where the power is, therefore more speed. A Vengance will not flex, so I don't think that is the answer. My personal experience with the Vengance is, that it's a really poor performer compared to ANY ss performance prop. Have you tried a 19"/20" Laser, Mirage or Enertia?

Hello
The speed measured with pitot speedometer. My alpha is 1.47. I will try out your suggestions. To many thanks to for the help!