Propping a 27 Fountain
#11
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Location: Cincinnati, OH
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I have same boat as you but 2002.. out of the factory was with a Bravo 1 24P 4 blades doing 65 mph half tank... now running Bravo 1 26P 4 blades.. 68-70mph with full tank and 3-4 persons onbord @ 4950 rpm.. i'm very surprised to see 5200 rpm with your 28P.. it must take forever to jump out of the hole.
#16
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Location: Lake St. Clair ,MI
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I have an 04 27 with the same set up. I run a 30 bravo and turn 5000 rpm with 2 on board light fuel at 69mph. Tried a 28 and was all over the limiter. Next step I am gonna try a p5x hydro but I think 70 will be the max for this combo. 30 bravo cruises way better than the 28 IMO.
Matt
Matt
#18
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You're right there. If you install a simple SmartCraft Gauge or put a computer on it you will see that your tach is slightly off. 5150 is the stock limiter in the 555. You have a 1.65 drive. With a light load of fuel and by yourself, you will bump the limiter a little if trimmed at about 5 or just barely, barely over 5 (say 5.1 or 5.2).
Jason did a bunch of prop and drive testing with that boat (SDFever).
Jason did a bunch of prop and drive testing with that boat (SDFever).
#19
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The tooth count difference on the gears from 1.5 to 1.65 is 2. Consequently, two teeth are equal to two inches in pitch if you're talking stock bravo 4 blade props. ..And those are about .7 less than stamped size. a 28 is really about 27.3 "real" inches.
#20
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I wonder why some have 28 pitch props with the 496 and some have 30? Same drive ratio and I would imagine same x dimension. I tried a 28 bravo and was on the limiter at 3/4 throttle. I can easily spin 5100 with my 30 but my speed seems right in line with everyone else. Oh well I guess like everyone says leave good enough alone but sometimes we can't!!
Matt
Matt