Speed of a 28 Powerplay?

[cowisl]

Hello Everyone,

Recently we purchased a set of 300 Promax's. They replaced a pair of 1996 2.5 245 carb mercs. The boat ran 74 on gps with three blade choppers and sportmaster lowers, 25" midsections. Props are turning out.

Initial testing with fleet master lowers,26 bravo I's, and 25" midsection is 73.7 MPH on GPS. The boat now has a slight chine walk and needs tab to reach max speed. Props are turning out. Any ideas? Should I lower the motors? Thanks.

[wideglide55]

Have you tried turning them in. The extra weight of the 300s may be the culprit,just keep experimenting with props, engine height,tabs etc.Sometime it can take a couple summers to get one set up like you want it.

[cowisl]

Once the props get done I am going to most likely lift the engines up a notch and go from there. Any other ideas besides switching the rotation of the lowers?

[wideglide55]

If it has started to chine because of a bow high attitude even with neutral or negative trim, maybe try a set of cleavers to see how it feels with them on it.Some v's run better with choppers, some run better with cleavers, depends on alot of variables. If it likes cleaver style,you may end up with 4-blade,through hub props like a set of custom Mazcos or Hydromotive,go to( offshoreonly.com) and they have tons of sets of props for sale,all diameters all pitches.Depends whether your hull needs bow lift,stern lift or a little of both.Took me two years to find a prop that my Eliminator felt right with, with the new 300.

[SCT]

Cowisl,
I'm setting up a pretty similiar boat to your rig. (I am rigging a 28' Cmate w/ dual 300X motors) I would be very interested in what props and setback you end up running on your boat. I was thinking about a set of choppers for top end and a pair of Trophys for all around play.

Thanks for any input,
SCT

[cowisl]

You may want to contact Brett at BBLADES. He is making me a set of props right now for the boat. His number is: (920)295-4435

[SCT]

Cowisl,
Thanks for the info. What props is he making for you?
Also, how much setback and drive heigth are you running?

[cowisl]

Since I dont know how to resize pics, I will give you a little info. The motors are on an armstrong bracket. They are mounted two down from the top, and I still think they need to go up.

Brett is making me a set of 28 Bravo I's labbed with vent holes.

[cowisl]

Ran the boat for the first time last weekend. Have about 6 lbs of water pressure, which seems low. When I look back, the motors are dumping water. Could the sensors be off?

Raising the motors up one notch to see if the chine walking stops.