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bbb
MMT 1000 Club
Joined: Wed Sep 02, 2009 2:54 pm Posts: 1554 Location: SW Georgia
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 MB Big Blade vs GD 3 blade on my 19ft boat.
Finally got some accurate numbers on these 2 props. The first time I did this back in 2010, my motor was stock. MB was 2mph faster than the GD 3 blade. I've been wanting to see what the mods did to prop performance.
Since I knew I didn't have a stuck prop, I took both props to the lake along with a rubber mallet, and a couple wrenches.
Load is just me(215), 6 gallons of gas and 2 batteries.
First run was with the Go Devil prop in deep water with hydrilla.
reset gps. Next run was with the MB Big Blade prop in the same deep water and hydrilla. Then I took the MB Big Blade through some shallow stuff.
Finally I put the GD 3 blade back on and went through the same shallow stuff and ran back to the ramp.
One problem I have is that at 27mph, my boat starts to porpoise, so I may have had a little speed left.
The motor never got over 3800 rpms with the Go Devil prop, and was cruising 25mph at 3600 rpms.
The motor was running 4200-4250 with the MB Big Blade, and was cruising 25mph at 3900 rpms.
When taking off, the motor needed ALOT less RPMS to plane off with the GD 3 blade.
I know the 3 blade is a little slower with a load, for my boat, but I'm gonna sacrifice that 1-1.5mph for less strain on the engine.
Also the GD prop is alot thicker and heavier than the 2 blade. Maybe next time I have them off, I'll weigh them. I would venture to say the GD prop is almost twice the weigh of the MB prop.
It was a nice afternoon to experiment.
_________________ 19x54 Seminole Extreme with a 35hp CDI GDSD. Mikuni. Marsh Mellow. Heads. Cam.
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Mon Oct 17, 2011 8:33 am |
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koda4u
MMT Pro Member
Joined: Wed Jan 21, 2009 10:43 am Posts: 72 Location: Tennessee with a Louisiana wife...
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 Re: MB Big Blade vs GD 3 blade on my 19ft boat.
Thanks for the extra knowledge... I just ordered a new 3 blade...
_________________ 18x54 CC Gatortail Huntdeck w/35GTR MM double barrel X Go Devil 16x56 w/35 SDGD -sold
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Mon Oct 17, 2011 1:17 pm |
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wbr9375
MMT Member
Joined: Thu Aug 11, 2011 9:40 pm Posts: 8
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 Re: MB Big Blade vs GD 3 blade on my 19ft boat.
thanks for the info. im running a 1st gen mb 35 with big blade prop on 16' xpress. pushin 4000rpm's @ roughly 27mph, lots of nose lift and porpoise without a load in front. Short of buying a new boat, any suggestions for improving efficiency and proformance?? thanks again
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Thu Dec 01, 2011 7:12 pm |
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Mike35
MMT Member
Joined: Tue Aug 03, 2010 11:22 am Posts: 39
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 Re: MB Big Blade vs GD 3 blade on my 19ft boat.
Will a go devil prop fit on a 07 mudbuddy 35 hypersport?
_________________ 1750GATOR TRAX &MB4000&MPE
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Wed Dec 14, 2011 3:08 pm |
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bbb
MMT 1000 Club
Joined: Wed Sep 02, 2009 2:54 pm Posts: 1554 Location: SW Georgia
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 MB Big Blade vs GD 3 blade on my 19ft boat.
_________________ 19x54 Seminole Extreme with a 35hp CDI GDSD. Mikuni. Marsh Mellow. Heads. Cam.
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Wed Dec 14, 2011 10:55 pm |
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Mike35
MMT Member
Joined: Tue Aug 03, 2010 11:22 am Posts: 39
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 Re: MB Big Blade vs GD 3 blade on my 19ft boat.
Ok thanks mine is the hex shaft not threaded.
_________________ 1750GATOR TRAX &MB4000&MPE
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Thu Dec 15, 2011 5:11 am |
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pooldoo73
MMT F.E.
Joined: Tue Jan 25, 2011 5:47 pm Posts: 886 Location: Plaquemine
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 Re: MB Big Blade vs GD 3 blade on my 19ft boat.
U r putting your motor under more strain by only being able to turn 3800 than with the prop that can turn 4200. It's kind of like going up a steep hill in a car and never down shifting. A lot more stress on engine by lugging it than by turning it up to designed rpm. Design if 4200
_________________ 18'x54"CC Hanko/ 36PD
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Thu Dec 15, 2011 8:31 pm |
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bbb
MMT 1000 Club
Joined: Wed Sep 02, 2009 2:54 pm Posts: 1554 Location: SW Georgia
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 MB Big Blade vs GD 3 blade on my 19ft boat.
Longtails run lower rpms since the prop is completely under water. I don't see them being any less dependable.
_________________ 19x54 Seminole Extreme with a 35hp CDI GDSD. Mikuni. Marsh Mellow. Heads. Cam.
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Thu Dec 15, 2011 8:38 pm |
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JD
MMT Addict
Joined: Wed Jan 21, 2009 6:54 am Posts: 563
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 Re: MB Big Blade vs GD 3 blade on my 19ft boat.
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Thats good speeds with a longtail.. Long tails don t have a gear reduction they will always turn less rpm with the same prop than a sd. If the engine is turning 3800 rpm underload you are fine. Higher rpm makes for faster wear. That motor likes 3900-4250 any faster it shortens the life of the motor.
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Mon Dec 19, 2011 7:47 am |
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