1990 Kevlar Gun, notched transom, 950 - 1000 HP, #6 Drives mounted 1/4" below the hull.....17x32 Four Blades. No slip getting on plane and Cruised 65mph at 3800 RPM.

Perfect, that's what I was thinking. 17" x 32 4blades, then send to BBlades if anything needs tweaked.

Thanks everyone!!!

OK, so first time it hit the water yesterday, could not get on plane. Any help out there??? SSM 5 - even with bottom 4 blade Merc props 16.5" diameter X 32pitch, was told "labbed" to more of a 34 pitch blade. I am thinking not enough diameter for how high the props are.

We plowed water not going anywhere at about 4500 RPMs, no chance of getting on plane, just couldn't turn the boat over to get up on top of the water. Tabs were buried too. Need help so I can get out there for what little season is left.

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Congrats on hitting the water, I'd say 17" diameter minimum

I had a similar issue with mine first time out, kept blowing the prop's out, then I remembered the tabs were about 1/3 of the way down, moved them up to neutral and the boat nosed over and I was off. Mine has 380's on it, and I know your higher X than mine.

We tried first with the tabs neutral or all the way raised. Then we buried the tabs and no change, thinking it's a diameter issue. I am also sure 5 blades would help, but I need to establish a baseline with 4 blades before spending big money on 5 blades.

Anyone run a 17.75" dia with this setup?

More diameter !! 17.5 min. bigger dia the better

5 blade test props available at BBLADES in known sizes. Plus experience to boot.......

You tried 4 blade 32's Labbed to more like 34's? Hmmm? I think we might be able to help.

Brett

17 3/4 x 27 4 blade 900/side. 3000 rpms.. 10 seconds on plane

Cup numbers horizontal along right hand side (.100+)
Other props (4 and 5 blades) with cup numbers in the .45 range = either could not plane at all or a 4500+ rpm 30 second burnout.

I have a pair of Herring 18 Diameter, 28 Pitch, 5 Blade, 18 rake props I may sell to you if you are interested. They have about 10 hours on them. They are the wrong prop for my 1994 Cigarette Top Gun with Arneson ASD7M drives. If you know anyone with18 diameter 6 blades, let me know. 29-32 pitch????? I also have some Mercury 4 blades that are worthless to me. I think they are Mercury 26 spline 15.5 - 16.0 inch Diameter, 4 blade 28 pitch props. Not sure. I could not get on plane with them and I have not looked at them since...... David....cell phone 281-743-5390