Trim Tab & Prop Questions
 

I have been working on an old Python 24/7 for the past couple of years. It is pretty well together and running reliably but I am struggling with some handling issues. Essentially, I get significant porpoising at low to medium speeds. I can correct it by digging my tabs in - but have Bennet Sport Tabs and they are miserably slow to respond.

Is there a prop design that will give me stern lift and reduce the porpoising?

Would a set of 280 K-Planes give me big improvements over the Bennets?

I placed these questions in the Budget forum because I already have way too much money in the boat and don't want to throw more at it without good results.

All feedback welcome!!

With straight bottom boats, its a trade off. You can put some weight in the nose, which will make it porpoise less at mid speeds, but it will make it harder to carry the bow at high speeds and cost you top end. A prop with more stern lift should be similar, better in mid range, slower on top. My feeling would be to really make the boat better, you might actually get a prop or tweak yours for more bow lift, and ballast the nose of the boat. This way, the prop has less effect in the midrange, and will carry the extra nose weight at high speeds. Experiment a little. You'll feel the difference with even a 25 lb weight plate all the way foreward.

Yes- k280's would give you some good authority. I ran a 26 Corsa with 380's, and they were fine, so long as you were careful with them. Dragging the tabs at mid/slow speeds is fairly normal in these boats, and is the cost of wanting higher performance.