Hey guys with 32ft 24degree hulls, whats the slowest mph you can stay on plane?
#1
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I’m putting a pair of 300 mercs on my 32 manta for transporting people to my island hotel. I have a 30ft boat in service now bringing people out from a small Town an hours ride away at 30mph carry 28 ppl and powered by a pair of suzuki 150s but it’s a 14degree hull that never climbs up on plane like a 24* hull does.
my 32 manta is approved for 22 people right now in its current original seating layout with one bench seat added and extending the seat in front of the center console full width.
as soon as the 300 Mercs are installed I will drop it in the water and put sand bags throughout the boat to duplicate 22 passengers and see how it performs. Then I Will add addl sand to mimic 30 passengers which is how many I can fit of i 86 the center console and make the captains station on top of the T top with some minor reinforcement.
I’m wondering how fast I will have to run it to keep it up on plane with all that weight in it. But locals run 17-19” props on these boats set up as cattle cars lol
the 18* boats are 40 ft long have a pair of 250s on them and they cruise at 30 mph. And will run @ 50mph empty wfo
will a 24* hull stay on plane at 30 mph or do they need to run closer to 40mph. Thanks for any info, Rm
tq I’m willing to widen the lifting strakes if it comes to that. I’m hoping I can run over 40mph and under 5k rpms on the 300s. Thanks again for any feedback guys...
my 32 manta is approved for 22 people right now in its current original seating layout with one bench seat added and extending the seat in front of the center console full width.
as soon as the 300 Mercs are installed I will drop it in the water and put sand bags throughout the boat to duplicate 22 passengers and see how it performs. Then I Will add addl sand to mimic 30 passengers which is how many I can fit of i 86 the center console and make the captains station on top of the T top with some minor reinforcement.
I’m wondering how fast I will have to run it to keep it up on plane with all that weight in it. But locals run 17-19” props on these boats set up as cattle cars lol
the 18* boats are 40 ft long have a pair of 250s on them and they cruise at 30 mph. And will run @ 50mph empty wfo
will a 24* hull stay on plane at 30 mph or do they need to run closer to 40mph. Thanks for any info, Rm
tq I’m willing to widen the lifting strakes if it comes to that. I’m hoping I can run over 40mph and under 5k rpms on the 300s. Thanks again for any feedback guys...
#2
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From: St. Pete Beach, FL
My 35’ with a 12’ pad will stay on plane down into the 20s with all of the little bennet tabs. 250 Suzuki’s turning out with the zuke props, which are large. In fact it doesn’t even have a discernible planing speed with the tabs down, it’s fairly flat from idle on up. It’s a relatively light boat at maybe 7600 dry.
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My 35’ with a 12’ pad will stay on plane down into the 20s with all of the little bennet tabs. 250 Suzuki’s turning out with the zuke props, which are large. In fact it doesn’t even have a discernible planing speed with the tabs down, it’s fairly flat from idle on up. It’s a relatively light boat at maybe 7600 dry.
so you run your tabs down at cruise to help stay on plane at low speeds?
#4
My 32 AT will stay on plane at 26-28 mph. I have had 11 people in it with 4 of them in the cabin. Total weight with people and fuel prob around 10500.
That is with drives tucked all in and Kplanes nearly all the way down. Its definitely not running efficiently at that speed though.
Gotta run it that way to keep under the LOTO 30mph night time speed limit
That is with drives tucked all in and Kplanes nearly all the way down. Its definitely not running efficiently at that speed though.
Gotta run it that way to keep under the LOTO 30mph night time speed limit
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From: St. Pete Beach, FL
yes tabs down while cruising. I think the most I’ve had would be 9-10 people, no performance issues I recall. I’ve also had 200+ gallons in it with a smaller crew.
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#7
My 34 NT will stay on plane at around 23 MPH with twin 400s and Bravo 1 22P props. Previously with 300s and 21P Rev 4 props, it would drop off plane around 33-34 MPH, and sucked coming out of the hole. No use of K-planes on either of those numbers. The 300s with Rev 4s would take 5K rpm to get out of the hole, very slowly, especially with a full belly (270 gallons) of fuel. The 400s with Bravos 1s pops out just under 3000 rpm with little to no bow rise, depending on fuel load. Again, this is with no use of K-planes. When Big Thunder rigged the 400s they raised the engines 1 hole from where NT rigged the 300s because they wanted to go to the B1s, which are a bit bigger in diameter than the Rev 4s. Boat all around handles much better with the Bravo 1s.
#9
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From: St. Pete Beach, FL
fug no. I wouldn’t be getting a 32’ boat with 30 people
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From: Palm Harbor, FL
Sure you can get that hull lightly loaded and happy in the low/mid twenties with tabs down and drives in. Loaded down to the Max it’s going to be a wallowing pig under 40. JMO based on experience with 3 or 4 blade I/Os, maybe better chance with outboards and five blades.
Last edited by Powerquest230; 02-28-2020 at 10:21 PM.




