Tried out a few Props, I think I need a new one

greg82255

Senior Chief Petty Officer
Joined
Oct 26, 2009
Messages
781
Hello,

I have a Formula 206 Spider with a newly built 383. I have finished breaking it in and so far have been able to try two different props and need to find one that is going to work right. I have a 14.75 x 21" stainless Mirage prop and a 13.75 (I think thats right) x 25" stainless Laser II. I have next to no control with the Laser II so I don't want to use it. I also managed to hit a rock with the Mirage on the first day so 2 of the blades have fairly decent size dents in them. I assume that is affecting its performance. The boat is about 22' long and weighs 3250 lbs without gas, and has a 40 gallon tank, so about 3500 with afull tank. Here are the #s I have gotten so far, all with GPS.

14.75x 21" Mirage: 5000-5100 rpm, 59 mph.

13.75x 25" Laser II: 56 mph @ 4500 rpm and barely any control. I'd say for sure it's lugging the motor.

Any idea what would work right? I was thinking probably a 23" but I don't know what kind to get. Also, if the mirage were not damaged, how much faster would I be with it? It has 1-inch long gouges in 2 of the blades. Thanks in advance.
 

steelespike

Supreme Mariner
Joined
Apr 26, 2002
Messages
19,069
Re: Tried out a few Props, I think I need a new one

What is the year and do you know the gear ratio?It is usually stamped on the outdrive.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,987
Re: Tried out a few Props, I think I need a new one

What is the year and do you know the gear ratio?It is usually stamped on the outdrive.

Ayuh,.... From 'is tagline,..
Champ II - 1986 Formula 206 Spider, Vortec 383 Stroker/Alpha One (until it blows up, then maybe a Bravo)

That'll be a 1.5:1,....

23" sounds 'bout Right for the pitch,.... donno 'bout which style to run...
 

greg82255

Senior Chief Petty Officer
Joined
Oct 26, 2009
Messages
781
Re: Tried out a few Props, I think I need a new one

What is the year and do you know the gear ratio?It is usually stamped on the outdrive.

Yea, it's a 1986 and 1.5 ratio.

Ayuh,.... From 'is tagline,..


That'll be a 1.5:1,....

23" sounds 'bout Right for the pitch,.... donno 'bout which style to run...

Yea I was thinking the same thing. I'm still playing with the motor a little and hopefully getting a few more RPMs out of it but I think 23" is going to be the best. I an hoping someone could tell me what style would work best - the Mirage worked well but the laser II was just awful.
 

Tail_Gunner

Admiral
Joined
Jan 13, 2006
Messages
6,237
Re: Tried out a few Props, I think I need a new one

Hello,

I have a Formula 206 Spider with a newly built 383. I have finished breaking it in and so far have been able to try two different props and need to find one that is going to work right. I have a 14.75 x 21" stainless Mirage prop and a 13.75 (I think thats right) x 25" stainless Laser II. I have next to no control with the Laser II so I don't want to use it. I also managed to hit a rock with the Mirage on the first day so 2 of the blades have fairly decent size dents in them. I assume that is affecting its performance. The boat is about 22' long and weighs 3250 lbs without gas, and has a 40 gallon tank, so about 3500 with afull tank. Here are the #s I have gotten so far, all with GPS.

14.75x 21" Mirage: 5000-5100 rpm, 59 mph.

13.75x 25" Laser II: 56 mph @ 4500 rpm and barely any control. I'd say for sure it's lugging the motor.

Any idea what would work right? I was thinking probably a 23" but I don't know what kind to get. Also, if the mirage were not damaged, how much faster would I be with it? It has 1-inch long gouges in 2 of the blades. Thanks in advance.

14.75x 21" Mirage: 5000-5100 rpm, 1.5 ratio 59 mph =13% slip

When you say 5100 i take it you have no rev limiter....Or was the enigne hitting the rev limiter..13% is a tad high...You have a strong engine on a small boat a 23p Turbo whould be a nice match agressive cupping high lift should lower the slip and at the same time lift the boat aka less wetted surface..Turbo does have a exchange program
 

greg82255

Senior Chief Petty Officer
Joined
Oct 26, 2009
Messages
781
Re: Tried out a few Props, I think I need a new one

14.75x 21" Mirage: 5000-5100 rpm, 1.5 ratio 59 mph =13% slip

When you say 5100 i take it you have no rev limiter....Or was the enigne hitting the rev limiter..13% is a tad high...You have a strong engine on a small boat a 23p Turbo whould be a nice match agressive cupping high lift should lower the slip and at the same time lift the boat aka less wetted surface..Turbo does have a exchange program

There's no rev limiter - I didn't install one and I don't think my ignition has one (Delco Voyager). I agree that 13% is high but I think that some of it can be attributed to the damage in 2 of the blades. The slip with the laser II is even higher - around 22%. I've never used a turbo prop - haven't heard of them. I'll look them up now.

I've also heard good things about Hydromotive - has anyone on here used one before?
 

Tail_Gunner

Admiral
Joined
Jan 13, 2006
Messages
6,237
Re: Tried out a few Props, I think I need a new one

Yes there a good prop by reputation i dont believe running deep in a outdrive is there fortay. Some here have played with them but i think there a surface prop of if you have a surface drive on a high horsepower boat..Well some luv them. But that brings to bear a very outstanding performer. Turbo 2+2 TH Series Same prop as the Stilletto baypro 11 from 0 to 59 nothing beats it in my book its as smooth as silk huge midrange far exceeds a comparable 3 blade...makes you feel like a huge four barrel is kicking in.

They have huge lift built into them creating less wetted surface hence speed..i run a 20 on a boat very similar to your and it is the mainstay prop all the time...and i have more than a few..:D Boy im biased but if you think about it 90% of your time will be a 2000-4000..and that four blade just shines there..Now i have lost 1.5 mph top end but that is trival in comparison..here's a pic of the lift..3500 lbs 19' 8 ft beam. That hull print is 28" wide..A 22p would do nicely

boat272.jpg
 

drivehard

Seaman Apprentice
Joined
Jun 2, 2007
Messages
47
Re: Tried out a few Props, I think I need a new one

I'm selling a 23" pitch Stiletto Advatage II SS that sounds like it might work perfectly!
$175 + shipping
IMG_2513.jpg
 
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