Bravo 3, 3x3, 4x3, 4x4

alldodge

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Searching the net I find all kinds of right ups. bblades seems to have the skinny, but I would still like to figure out what's best for my issue. Have 4 sets of 3x3 B3 prps, 22, 22 cupped, 24 and 26 pitch

Current, 11K single engine cruiser (Formula 27PC). A 502 producing 530 or so HP and 600 ft lb torque. Have a Bravo XR upper and Bravo 3 lower with 2.0 ratio. Have a 3x3 prop set 2ith 26 pitch set, comes out of the hole ok, wouldn't mind more, and cruises at 3600 to 3800 rom doing 34 to 36mph with about 20 percent slip. Have about 220lbs of anchor chain in the bow. WOT is at 5050rpm at 46 to 47 mph, all speeds is with gps.

Looking for hole shot and cruise range, could care less about top end. Have found no one which says lab finish is money well spent in my area of boats. Wouldn't mind spending the money for another set of props but not for one second shorter hole shot, reducing prop slip to under 15 percent might get my attention.
 

tpenfield

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I think part of the problem is 11K lbs being propelled by a single engine/outdrive. A 4x3 24 P might be the way to go, but your engine may end up at around 5300 RPM, if that is OK..

There is some info on the web, but not many real life tales being told, since it is a steep investment to try out different prop sets.

I have 26P 3x3 sets on my boat and I can easily blow them out on a hole shot, so I have to bring the throttles up in steps. Are you sure your boat is 11K ? I thought the spec's for the 27PC were more in the 9K range . . . but maybe that is dry and no gear. I think I am running about 11-12K loaded on my 330.

Prop Slip for my boat starts out at about 26% for low end planing speed (22 mph) and goes down to about 13% at WOT (52 mph) 1.81 drive ratio

propslip1.png

20% slip with a single prop on an 11K boat might actually be good.
 

Tail_Gunner

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Jan 13, 2006
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Searching the net I find all kinds of right ups. bblades seems to have the skinny, but I would still like to figure out what's best for my issue. Have 4 sets of 3x3 B3 prps, 22, 22 cupped, 24 and 26 pitch

Current, 11K single engine cruiser (Formula 27PC). A 502 producing 530 or so HP and 600 ft lb torque. Have a Bravo XR upper and Bravo 3 lower with 2.0 ratio. Have a 3x3 prop set 2ith 26 pitch set, comes out of the hole ok, wouldn't mind more, and cruises at 3600 to 3800 rom doing 34 to 36mph with about 20 percent slip. Have about 220lbs of anchor chain in the bow. WOT is at 5050rpm at 46 to 47 mph, all speeds is with gps.

Looking for hole shot and cruise range, could care less about top end. Have found no one which says lab finish is money well spent in my area of boats. Wouldn't mind spending the money for another set of props but not for one second shorter hole shot, reducing prop slip to under 15 percent might get my attention.


Lab finish for low end grunt and midrange.......Hmm one would think diam and blade surface area. But prop's are BBlades game and he does have the credential's.
 

alldodge

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The 11K might be a little high but don't think its that much. The book said 9.5K dry, then add the Gen, 104 gallons fuel, water (24 tank, 5 hot water) and gear, getting close. I'm not getting any blow out when taking off and I'm putt it all the way, no hammer just a smooth steady all the way.

Prior to the rebuild I could trim the drive up more then now. My assumption is the stern was a heavier with the water found in the hull and foam. Not that it's a bit lighter the weight of all the chain in the bow is causing the boat to tip over sooner.

On his site the XR props appear to all lab finished, but the XR's are also available in odd single pitch increments, so a 25 is available
 
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