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Conventional V-bottom hydronamics question..........

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Old 12-20-2007, 02:51 PM
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Default Conventional V-bottom hydronamics question..........

* PLEASE don't let this thread turn into a stepped hull VS. non-stepped hull bashing issue!

There's no dispute that some people like conventional (non-stepped hulls) and some people like stepped hulls. There's also no argument that they both have their good/bad points, I have an intrigging question.

99% of the time, a stepped hull is faster than a non-stepped hull-- so why are some non-stepped hulls, like Velocity Powerboats as fast or faster than a stepped hull in it's own class?

I know it's not "rocket science", I do understand why a stepped hull is usually faster, because of less drag from the steps. So why is a Velocity (non-stepped bottom) so fast? What makes it so fast compared to other stepped hulls in its class?
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Old 12-20-2007, 03:26 PM
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The Velocity has large pad at the back. The boat runs with the pad on top of the water instead of a standard V that cuts through it.
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Old 12-20-2007, 03:42 PM
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Also I would think weight still plays a big roll in the speed.
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Old 12-20-2007, 05:10 PM
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Also I would think weight still plays a big roll in the speed.
I completely agree, however the weights of these boats are similiar to their competitors.
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Old 12-20-2007, 05:11 PM
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Quote:
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The Velocity has large pad at the back. The boat runs with the pad on top of the water instead of a standard V that cuts through it.
I wonder why other conventional V bottom builders aren't doing the same?
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Old 12-20-2007, 05:14 PM
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I wonder why other conventional V bottom builders aren't doing the same?
Because many people (like me) are looking for a boat that rides well in the rough. I true Vee will cut through the big waves. I pad will slam on top of them.

Everything about boating is a trade off. Speed vs. ride, etc.

Smooth ride, fast boat, low cost. Pick two of the three!
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Old 12-20-2007, 05:58 PM
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Like Clay says there are compromises. I spent a lot of time time running different 30 Velocity's and enjoyed them very much. The 30 is a drivers boat it is fast and nimble, carries weight well, and importantly demands your attention. They are completely capable of running with any rough water boat in the rough if the driver is experienced. It does ride harder. You could think of it ride wise like comparing a vette and a caddy. Both are nice with different strong points.
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Old 12-20-2007, 05:58 PM
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WHOAH Gerrard!! You opened up a can here!

There are a LOT of things that matter.

1. Weight is a bigger factor than anything.
2. The step itself is not what makes a boat faster. Its the natural pitch or trim that it places the thrust, as well as depth in the water in relation to the weight being pushed or displaced.
3. There are so many bottom designs out there, that you CAN'T generally title one as better (fast/ride/efficiency) than the other based on categorical design. You have to take into account strakes, hook, rocker, tabs, etc. etc.
4. Multiple steps are actually slower a single step; and a straight bottom should be faster. (Given ALL things equal, but how could you accomplish that?) Think of it in plumbing terms. If point A and point B are exactly 8' apart, and you have three equal diameter tubes to pour 2 gallons of water through; which one do you think is going to empty First? Second? Third?
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Old 12-20-2007, 06:07 PM
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Quote:
Originally Posted by Clay Washington View Post

Smooth ride, fast boat, low cost. Pick two of the three!
When did "low cost" become an option??

I guess I missed that thread / didn't get the memo.
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Old 12-20-2007, 06:10 PM
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As far as different manufactures doing pads many do. There are variations in deadrise and size of the pads. Fountains, and numerous others have some variation of a pad. Some cats even have pads.
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