I was really going to stay out of this one. But I run a 150 on my 222ccp. It planes out just fine and top end is all I really need. I run 30 miles off shore in the mid Atlantic. Most of the time the wind is blowing. So my point is. I’m not racing I’m fishing my fuel economy is better with the new 150 then it was with my older 175 2/3 better. So in realty. Who really cares if I get on plane in one boat length or 2 boat lengths. Also with seas at 3 to 5 feet with an interval of 6 sec. why would I run faster then what is comfortable. My over all point is to many get lost in optimal instead of what is practical. The biggest thing with a 0 to 14 degree dead rise over a 20 or more degree dead rise is how you will use your boat. If I was fishing in sallow water all the time a 0 to 14 degree dead rise would be a better choice. If running off shore a 20 or more degree dead rise would be the better choice. So what matters more, is get your boat to fit your use. But the original question is a very good one and is not understood by a lot of people hearing people talk about classic Aquasports. I know I learned a lot as to when a number of these chances happened with a great classic boat. So if you are getting one or two or three. do what is the most important. Injoy it.
LR - you are right to a point, but boats do not plane from the stern, they plane from the front. That's why Coburn put those lifting strakes in the front of the 22-2 in the early 70's - they help the boat plane faster. A compaint about the early flatbacks was they did not plane quickly - they did more of a rise with speed. The reason flatter semi-V or flatbottom boats plane quickly is not due to the deadrise - it's really more that the bow lifts quickly and then the stern comes up to follow. I've had true flat bottom boats that plane almost instantly because the whole hull lifts at one time. Some Pro-Crafts, Larsons, and others even have sponsons in the front to help them plane, and then a deeper V futher back for a smoother ride once on a plane. Most deep-V hulls (say 20 degrees deadrise) at the transom are a LOT more than 20 degrees at the bow, so there is almost no lift there - unless you add some lift with strakes. Without the lift from the horizontal strakes in the bow, these boats are very slow to plane. Grady-White and some others use deep-V hulls with several strakes to get the hull on a plane quickly, yet allow for the more gentle entry of a deep-V in waves. Think stairstep physics here - the water lifts on the horizontal plane, but slips on the vertical plane. This was a key benefit from the old wooden lapstrake boats - they had many 4-5 inch strakes that helped lift the hull. For example, the Chris-Craft Sea Skiff (a lapstrake boat) would plane quicker and stay on a plane with less power or at a lower speend than the comparable Chris-Craft models like Cavalier, Commander, or Constellation that did not have the benefit of the strakes to provide lift, but had a similar deadrise at the stern. So as the EPA says, "your mileage may vary." The common wisdom that flatter bottoms plane faster and run faster with less HP and deep-V's run smoother in rough water but take more HP is generally true - but you can mix design features and hybridize some aspects to get some advantages of one with the other - it's not always either-or; sometimes it's one-and-the-other.
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Topic: What is a flat back (Read 10511 times)
