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Thread: length vs width

  1. #1
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    Default length vs width

    which boat do you think would out perform faster speed and better handling with same motor ,same height?

    # 1 boat: 13'.5" x 48" bottom semi V with 16" pad and 6" set back .

    #2 boat 14' x 44" bottom semi V but less V than boat number 1, 14" pad and 6" set back.

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    It depends a lot on the size of motor and the weight of the whole rig.

    For every weight, CG location and speed, there is a correct pad width. More than that or less than that and you are slower. More width creates more lift, so if you are heavier, you want the wider pad. If you have more power and are going faster, a narrower pad width is what you want. So it's a matter of matching the power you have with the weight and CG, and how fast you are planning to go.

    Hope that makes sense.

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    It would be a hard call without all the specs but generally if fast enough to really lift & the wind to make a difference the narrower boat would likely be faster straight but not that likely to out turn the deeper wider boat.

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    Unhappy

    I think i understand what ya'll are saying. The reason I asked is I have boat # 2 but someone wants to trade me # 1. 2 brothers owned the above boats and there is about 10 lbs weight difference between the brothers. Boat # 1 ran about 1 mph quicker when racing each other several times. What I have been told is that boat # 1 will hold the pad at half throttle. The boat I have you have to drive it through until it on the pad and I mean hold on.My prop is slipping but able to get 44.8 mph on gps with stock prop.. Tomorrow I will install tiny tach and see rpm its turning. Motor is 40 merc 2 stroke 3 cycl.w/ trim. Is this a decent speed?

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    I suspect you could go MUCH faster by concentrating on "hopping up" your Merc.

    That Merc is the same basic motor as the 60 hp triple, the difference being carb sizes and tuner (in the tower). Both are easily changed for a substantial powerincrease. There MAY also be a difference in the port timing, but historically this is NOT the way Merc and others de-tune a motor to make a lower powered model; they start with the max power model, then strangle it to produce the lower powered models.

    Jeff

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    Quote Originally Posted by Yellowjacket View Post
    It depends a lot on the size of motor and the weight of the whole rig.

    For every weight, CG location and speed, there is a correct pad width. More than that or less than that and you are slower. More width creates more lift, so if you are heavier, you want the wider pad. If you have more power and are going faster, a narrower pad width is what you want. So it's a matter of matching the power you have with the weight and CG, and how fast you are planning to go.

    Hope that makes sense.
    I would like to get the boat in the high 50's

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    Hopping up the motor, then, would be your best bet. The 40, 50 and 60 hp new Merc triples are all 60 cubes. The difference is in carbs, tuner, etc.

    Jeff

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    Quote Originally Posted by Nason View Post
    I think i understand what ya'll are saying. The reason I asked is I have boat # 2 but someone wants to trade me # 1. 2 brothers owned the above boats and there is about 10 lbs weight difference between the brothers. Boat # 1 ran about 1 mph quicker when racing each other several times. What I have been told is that boat # 1 will hold the pad at half throttle. The boat I have you have to drive it through until it on the pad and I mean hold on.My prop is slipping but able to get 44.8 mph on gps with stock prop.. Tomorrow I will install tiny tach and see rpm its turning. Motor is 40 merc 2 stroke 3 cycl.w/ trim. Is this a decent speed?
    The wider pad is providing more lift at lower speeds, which lets you get up on the pad easier. As you go faster you don't need that lift. Assuming that the previous owners were running about the same power that you are, and you are planning on going a good bit faster, then the narrower pad is probably the better choice for straightaway speed. If you are going a good bit faster you aren't going to need the lift that the wider pad gives.

    Everything is a compromise, and no boat does it all. As you have found, the wider pad is a lot nicer at lower speeds, but it's going to cost you on top end compared to the narrower pad.

    As others have noted, engine mods will result in a lot more speed. What you want to do is find others that are running your boat with 60hp and see how fast they are going, and, do they have any stability issues running that fast?

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    If switching the motor from a 40 to a 60 is that easy then yeah it would make some real difference. There is a catch or 2 tho, That doesn't automatically mean your going to gain way more RPM's or speed, more likely acceleration. If you have a rev limiter on it then maybe only acceleration [unless you defeat it] What you will need is the right prop.. all other things being good [?] that will be what brings it together. Good Luck, careful at speed.

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    [QUOTE=Yellowjacket;115607]The wider pad is providing more lift at lower speeds, which lets you get up on the pad easier. As you go faster you don't need that lift. Assuming that the previous owners were running about the same power that you are, and you are planning on going a good bit faster, then the narrower pad is probably the better choice for straightaway speed. If you are going a good bit faster you aren't going to need the lift that the wider pad gives.

    Everything is a compromise, and no boat does it all. As you have found, the wider pad is a lot nicer at lower speeds, but it's going to cost you on top end compared to the narrower pad.

    As others have noted, engine mods will result in a lot more speed. What you want to do is find others that are running your boat with 60hp and see how fast they are going, and, do they have any stability issues running that fast?[/QUOTE

    Both boats had 40hp merc 2 stroke 3 cycl. Boat # 1 with wider pad ran 51.5 on gps all day long. Boat # 2 ran w/ smaller pad ran 50.3 all day long. Give or take a couple of points. Same motors and props w/ same pitch and dia. The only difference now is that I have a long shaft and its jacked up like a short shaft, which is what they had short shaft motors.

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