Offshoreonly.com - Conventional V-bottom hydronamics question..........

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Before this thread makes a wrong turn, I just want to say thus far it has had some very good points brought out and I have enjoyed reading it. Welcome gramp but I have to ask what Velocity you are talking about that has a narrow beam? I have a 280 and the beam on it is 8'2", and the 39 that is so fast with the 700s in it has an 8'3" beam. A 38TS Top Gun has an 8' beam and a 38' fountain has an 8'6" beam, so I would say they are average if anything. Also I'm not sure what Paradox means by the stakes being designed to push the water away from the boat, my 280 has stakes like you drew for example A.

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Originally Posted by hpoffshore (Post 2379741)

First-off...Time is not quantified in "plethoras"; and Fountain made a 42 single step, not a 38.

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Originally Posted by mccaffertee (Post 2379742)

Well, I am guessing that Fountain knows something that the single step guys haven't learned yet.

Thank you very much for the insight gentlemen. :D

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Originally Posted by VelocityMark (Post 2379753)

Both "V "hulls have a beam of 8'.. right, has a narrower surface.
Bottom right, allows more air, better lift, but harder when lands on wakes. geting the curve flatter in the rear and "out"... will tend to push the water out instead of straight back. The location of the curve will provide bow. mid or stern lift. I have an old INfinity, one of the last made with variable "rib" / strake design. one of the fastest 26' (with 454)and rides like a Apache in rough. (lol.. I can see all the Apache owners geting after me for this one )
Attachment 315797

Read My Next Post..........i Got Another Question!!! :)

OKAY................. Here's another question...

Why does the 32' Advantage not need tabs, even running in rough water? I have never been in one, but every offshore boat I have ever been in needed tabs in rough water.

The 38 TS TG didn't need much tab at all. I think it's one of the best rides out there that I have ever been in. Boat flys very level.

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Originally Posted by marylandmark (Post 2379941)

That pic on the bottom right with the arch looks like you have the shakes bro- get another drink before they get too bad!!

J/K- I know drawing with a mouse it hard! :drink:

No prob. :) But sorry Mark,, can't drink.. :mad:
Doctors order. Something with the pencrious chitt. It's shut down,, no cure.. no drinks..

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Originally Posted by Sydwayz (Post 2379641)

I'll agree.

It also has less hull in the water a.k.a running surface; which provides for reduced drag.
A 26' boat and a 28' boat with like bottom designs that weigh EXACTLY the same; down to the ounce, with IDENTICAL power... Which one will be faster?
The one with the least drag.

true. using skater as an example the 28 is heavier longer and wider, yet with the same o/b power is faster than the 24.
i find this impressive.

as well as this

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Originally Posted by Sydwayz (Post 2379716)

Not really on single step 38+ footers. How long did he keep them; a year? Two?
That is, before moving on to multiple steps... where he has spent a plethora of time dialing in.

There is more to it than that. The Fountain Factory is 2 hours away and so is Joey Griffin - my engine builder and most know the relation of Joey Griffin & Fountain. That said, I have spent some time down there to ask questions. Fountain uses twin step design because they want their boats to be the fastest / safest boat they can build.

But the following is what I learned at Tres' school:

The single step hull design makes for a skittish ride, plus the pivot point when turning is farther forward. Multiple steps generally ride better and are more predictable in turns and the pivot point is rearward (where the weight is) and thus turns more confidently.
I assume that if you want a better riding more predictable turning boat especially at high speeds, then most builders are going to use and "dial in" what works better.

If you doubt me, I'll be glad to refer you to Tres Martin.

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Originally Posted by Semper Fi (Post 2380029)

OKAY................. Here's another question...
Why does the 32' Advantage not need tabs, even running in rough water? I have never been in one, but every offshore boat I have ever been in needed tabs in rough water.
The 38 TS TG didn't need much tab at all. I think it's one of the best rides out there that I have ever been in. Boat flys very level.

Alot of this has to do with the builder and balance.
When a boat hull is designed, it is done with certain things in mind, usually something like this:Twin 525's & Bravos, a cabin, and a cockpit.

In a readers digest version: The boat is tested and minor changes are made so the boat is balanced. Everything that went into that boat - the weight of components & location was thought out so the boat would be balanced. Ok, so you you have a properly designed/balance boat right from the designer.
Now the builder wants to sell boats to more people so they add, A/C, Toilet, hot & cold water, 5000 watt audio system, shower and more creature comforts. What does that do to the original balanced design of that boat - likely nose heavy? Maybe they installed all creature comforts on the port side - refrigerator, AC, Stereo, hot water. . . . . .what about balance??
or,
Builder installs mega HP motors, #6 drives and adds 3 more batteries. What does that do to the original balanced design of that boat - likely stern heavy?
Ever heard a builder say: "If you want A/C then I need to add 2 more batteries so the boat stays in balance"?

I am not sure who designs all the big names in boats, but AT is a Harry Schoell design and the Cig Top Gun is Michael Peters.
Now, if Cig or AT gets an order for a boat, and the guy wants big power and #6 drives, do you think either of these manufacturers call the designer and see what needs to be done to offset the added weight so the boat is as the designer intended?