Question for the prop experts...think I need a change

[Russ13100]

New to the performance boat scene (but not new to boating) and so my prop knowledge is not great.

Here is what i'm running:

25' Sunsation Aggressor
502 MPI 415hp
Bravo 1 drive
4 blade 26 pitch prop
Usually 1/2-3/4 tank of gas & 2-3 adults.

On gps i can get 60mph at WOT, a touch higher if conditions are ideal. At this speed im turning 4500-4600 rpm, so i know there are about 600 rpms being left on the table. I feel with this motor pushing the boat it should be in the upper 60 mph on gps.

The 4 blade prop is on there because the previous owner preferred with for the stability it added, had a 3 blade on before that and he reports that it chine walked pretty bad at WOT.

So my question is, what pitch should I look for in a 4 blade to get more use out of the remaining rpms? Is my feeling that it should be a high 60 even maybe 70mph boat out of line?

Appreciate the help!

[go propless]

I would try a 24B1 4blade. That will bring your rpms up and may increase your speed, and will still keep the performance of the 4 blade.

[Griff]

Try a 24 Bravo 1 4 blade or have your 26 labbed by BBlades. BBlades also has a test program and you could try some other props from him, based on his recommendation.

[Duffer]

Originally Posted by Russ13100

New to the performance boat scene (but not new to boating) and so my prop knowledge is not great.

Here is what i'm running:

25' Sunsation Aggressor
502 MPI 415hp
Bravo 1 drive
4 blade 26 pitch prop
Usually 1/2-3/4 tank of gas & 2-3 adults.

On gps i can get 60mph at WOT, a touch higher if conditions are ideal. At this speed im turning 4500-4600 rpm, so i know there are about 600 rpms being left on the table. I feel with this motor pushing the boat it should be in the upper 60 mph on gps.

The 4 blade prop is on there because the previous owner preferred with for the stability it added, had a 3 blade on before that and he reports that it chine walked pretty bad at WOT.

So my question is, what pitch should I look for in a 4 blade to get more use out of the remaining rpms? Is my feeling that it should be a high 60 even maybe 70mph boat out of line?

Appreciate the help!

I had same boat '92 25 Aggressor with a 454 Mag. 1.5 gear ratio Ran a 23 pitch Mirage - 5200 R.P.M. 69 M.P.H. - Chine Walked Like Crazy. I put IMCO Dual Ram Hydrolic Steering on the Boat - Put in a new Motor - 454 bored 30 over with a 1/4" Stroke and a Intercooled M-1 Procharger - 750 H.P. Now run a 30 Pitch Brovo 1 Prop to about 5500 - 6000 at 92 M.P.H. Chine walk is still there but it is controlable with the Steering. My suggestion would be put steering on the boat and prop down to a Three Blade if you want to go 70.

[risingsun]

Ive owned the 25 for 6 years, steering and either have your 26 labed or run the three blade. need to lock your port tab so it stays level with the bottom of the boat. I'm pushing 800hp now but I started with your same setup. I've pushed it to 102 and what a ride.

[silent lucidity]

Heres the gig.. 312 fastech,twin 454mag mpi, 28p bravo 1's.
great hole shot can even pop up 2-tubers fast. Boat runs 70mph but is bouncing on the rev limiters.. I can tell she wants to go more... I know first off re-map ECM bump rev limiters to 5400 or so+ some extra yummies...
Is it worth the bucks $$$$ to change the pitch up one and pocket blades or even thin leading edge. Or am I waisting money.. I have not put my EMI offshores with S/S risers on yet will do this winter along with Vortch Breathers.....
give your thoughts ole' boating buddies.

give me fuel- give me fire-give that which I desire!