Unconfigured Ad Widget

**Dust33** · 10-25-2018, 04:15 PM

Hello Dave,

�Minimum Required Hull Length� is more of a runabout thing as far as the rules go, but the builders can comment as to what lengths / dimensions are best suited for a particular hydro class.

For more hull & engine details, suggest starting with rules which are accessible through APBA website.
https://www.apba.org/rules

For Stock, go to the Technical Manual, but for other kneeldown categories go directly into their category rules (for Mod (pgs 11&12), Pro (pgs 14-16), & Jr (pg 13)).

In stock tech manual, begin by looking through pages 14 - 17
https://www.apba.org/sites/all/files...4-28-18%29.pdf

Hope this provides fuel for further questions!

**Shorewood** · 10-27-2018, 12:20 AM

I�m curious right along with Dave, with similar questions about hulls. The technical rules for stock outboard really go to weight and some dimensions for a couple of classes (trap measures for A, etc., and afterplane length for 300ssh). Beyond that there isn�t a lot to go on. My situation is I have a 102 and would like to know what type of hull is recommended. I weigh 200 and I know weight is a factor, but what are typical or optimum dimensions for a hull running a stock 102?

**pops67g** · 10-27-2018, 04:10 AM

Technical rules supposedly are there to level the playing field so everyone has an equal chance at success. We have a number of boat builders that produce very good boats that fit within the rules. Go to a race or two and watch to see what make runs up front most often. Guys that win races regularly
are good drivers, have a lot of experience, and like to use the best tools for the job.

**ZUL8TR** · 10-27-2018, 05:57 AM

Originally posted by Dave Cofone View Post

Hello again, newbie here with another question. These outboards are the new 'thing' on my mind. Since Barbara Brink invited me to my first SO race these little boats have captured my attention. As cool as they are the number of classes is confusing to me. My experience is in inboard and Vintage. There is a minimum hull length and a maximum engine size.....simple. But what confuses me about stock outboard is what are the minimum hull lengths that are required to run a certain engine size..? I see a class C hydro can also run in the 300ssh, C and mod classes. So what exactly is the minimum hull length for a class C hydro...? What about a class B hull.....? Indulge me as I am in the learning stage, many more questions to come....I'm warning you in advance.

Have you been here?:

https://www.apba.org/categories

Also here is a very informative manual by GrandpaRacer on hydro basics:

https://hydroracer.net/2015%20Hydro%20basics.11.7.pdf

Edit on page 14: the example of power increase to go 2 times faster uses Total drag vs speed ^2 relation, actually it is Total drag vs speed^3 so to go 2 x faster requires 8 times the power to the water to over come total drag. Grandparacer informed and said he will correct. Also at same temperature water is about 780 times more dense than air so water drag very predominate to these race boats .

**rumleyfips** · 10-27-2018, 09:07 AM

Look at boats for sale. Some people include the length, afterplane, bottom width etc.

**Shorewood** · 10-27-2018, 11:40 PM

Some examples of basic dimensions some of you run in B, C, and D hydro would be really good (length, width). I'm new and trying to get a feel for what to look for in a hull, and any advice you can give will be helpful. I'm even curious about how you store you hulls for the winter, if you do anything special to support them. Having been to a few races I have some idea about hulls, but when I see boats for sale they often reference what class they're intended for, and about the only thing I can determine is that length (and as a corollary, weight) is the primary difference in hydros between J, A, B, C, and D, for instance.

**ZUL8TR** · 10-28-2018, 03:05 AM

Treads from the past on dimensions, there are more I just hit search with "hydro dimensions":

https://hydroracer.net/forums/forum/m...ensions?t=8853

https://hydroracer.net/forums/forum/m...-physics/page2

**pav225** · 10-29-2018, 11:06 AM

Dave,
You are in a great area for boat racing. Reach out to the members of Seattle Outboard Association (SOA) and try to go to a Club meeting. Better yet, go testing with someone this fall. Quite a few SOA members get on this website, so I'm sure someone will extend you an invite.

We always recommend buying used equipment when you get started. Once you have an idea what class you are interested in, shop around and ask different members if they know of good used equipment for sale. Often times you can get a great deal on a boat, motor, prop package. Be sure to get input from a few different people as you hone in on a class.

If you are interested in a new boat, contact Jerry Davids or John Runne. Both make fast, well built, boats.

**DeanFHobart** · 10-29-2018, 03:03 PM

Hello Dave Cofone,

New Jersey is also a good boat racing region and other places fairly close. Are the Kayaks you build �Stich and Glue� or traditional frame, stringers and plywood skin?

If you build your own make sure to get current design plans or a frame kit. Be sure to talk to current boat racers in your area for help. They will be glad to help you I�m sure.

The reason that I asked about your kayaks is that our typical all wood outboards are traditional frame, stringers and plywood skins.

Good luck with your racing pursuit.

Regards, Dean Hobart

**rumleyfips** · 10-30-2018, 06:31 AM

Fralick Boats and Sorensen Woodcraft have dimentions on their websites. They both sell plans.

Unconfigured Ad Widget

Announcement

Boat length, engine size and many more questions to come.

Boat length, engine size and many more questions to come.

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment