SUPERBASH

24's & 30's
-Since they are the same hull design....

1) Does anyone think the K-Planes even in the retracted position are killing the 24's & 30's boat from lifting???

2)Is the stepp hull design just not made to provide natural lift???

3) Even with a good bowlifting prop...it takes full trim for this thing to get any serious speed. Do the straight Vee (older) Superboats have this same problem???

djtalon

BASH
i have an 83 24 with twins, 12 inch setback. Havent been out in the boat only a couple of times but it has absolutly no bowlift problem. Actually i use a bit of tab to keep her down. I also do not have k planes. You might wanna also ask gassticks he has a twin boat and with kplanes and would know if it flyies.
Check when you are running with the tabs totally retracted are the tips hitting the water? You might have a sort of step bottom leveraging problem because of the setback. If you have some pics with some measurments i can run a simulation on it at work and might get some theoretical data for you.
later
dj

SUPERSTITIOUS

Bash if you look closely at speed if you play with the tabs you can actually see them make contact with the water by the change in spray off the back. I had the 280's and I also had the mechanical indicators which I marked for when they were parallel. to the bottom. On my boat they came up quite far and on my opinion were not an issue with contact. I often was wondering about the Arneson Rocker plates. They actually mount flush with the running surface and when talking with them they stated that they actually create a bit of bow lift by the suction affect when they are trimed up. Thats Arnesons pitch anyway

Pat McPherson

Hi Bash,
I doubt that the K-planes have any effect on the boat when they are full up...
As you know, my boat is a straight V with the prop shaft deep in the water. My boat does not have a bow lift problem.
It does take more trim to gain speed with a Bravo I 4 blade vs. a Mirage + 3 blade. But that may be do to the fact that the 4 blade is also larger in diameter. I can feel a sweet spot while trimming and if I go too far the rpms go up, but the speed comes down.
Bash, have you calculated your slip?
If your under 10%, that is about as good as it gets for a deep V...
Your running dam near 80mph Gene.
I can't imagin you can squeeze much more out of her...

SUPERBASH

Watch Bash's latest Vid & note the "turbulence" coming off the transom where the k-planes are mounted.
-OhZone The k-planes act as brakes & force the bow down...causing a loss of speed on any performance boat. I never use them unless one at a time to correct the list of the narrow hull or to compensate for a heavy passenger .

-Pat The larger the diameter prop..the bigger the surface area...the better bowlifting capability. My 14 1/2" 3 blade Chopper carries the bow under trim with higher speeds far better than the 13 3/4" 4 blade TrophyPlus. My slip is at 10%. Its just the motor has to be trimmed to the moon to get speed. If I raise the motor vertically (higher propshaft centerline) slip goes up...speed goes down.

dj- see what you can do.

SUPERSTITIOUS

Bash; I'm with you on the tab effects but I just threw that statement in about the Arneson rocker tabs cause when discussing the possibility of useng the Anreson bravo conversion and discussing bow lift on a long narrow v-hull the guy was telling me about their rocker plates, how they are mounted and how they helped bow lift to a point as they were trimmed up. Check out their website. they even provided a comparison chart. I personally felt it was a bit of a sales pitch but am stating what they told me FYI. just something to ponder. when I ran the Lightning ET I definately noticed better bow lift and could raise the jackplate more so. I think if I kept experementing I would have tried a chopper style prop with a bit more blade area cause the trophy plus was far superior for me midrange.

SUPERSTITIOUS

Could that be splashing coming from the water hitting the notched transome?

Pat McPherson

Hi Bash,
I did watch your video. Great footage!
I am not sure that the spray/turbulence is from the tabs though...
Stormrider would gladly trade his shorter ones for yours if you believe your 280s are scrubbing speed...
Personally, I think your better off with the larger tabs in rough water.

FASTERDAMITT

Here's a link to what OH's talking about. To me the only difference is the Arneson is mounted flush to the bottom and it will raise higher than a K-plain. When raised it creates a vacuum under the plate?

http://www.arneson-industries.com/Ar...r%20Plates.htm

z.zuperboat

Everybody wants bowlift including myself. I know the step bottom was designed to run faster with less trim and they do. In rough water to much bowlift will be a bad thing as you will be unable to keep the nose down. Thats Y the 30 is such a great rough water boat. So where does the quest end, and yes I also want my cake and eat it too.