I know, I know... this subject is beaten to death from time to time. I just finished reading through several searches. It is fairly evident that resulting change in performance when adding say 12" boxes can vary wildly depending on the hull length, design, weight, center of gravity location, etc...

So here's my question. By chance, does anyone know of a 292 Fastech Formula or similar twin stepped, twin small block, 24 degree V-hull that has added setback boxes? Did it like the change? Thanks.

ttt

...or am I going to be a guinea pig.

if i remember right the 292 is not notched on the transom, if you can get 12" of set back it will help some maybe 1 or 2 mph at most, now if your boat can get onplane with 3 blade props then your drives are a little on the deep side then if you run the stellings box and raise them you will pick up maybe 3 or 4 mph, if your boat wont get onplane with 3 blade props then your drives are a little on the high side and the raise on the boxes wont really help much. just my 2 cents !!

Thanks for the 2cents H2Xmark. I believe my 292 has a notched transom. The running surface (like where the drain plugs are located) is stepped forward probably 5-6 inches. My boats gets on plane with a little slip using 4-blade bravos. I think the x-dimension is pretty average.

To all - At this point I am really not looking to gain much speed, more looking at improved handling at both low and high speed. Like low speed planing. Right now to run low speeds for tubing I need a lot of tab and the props like to cavitate. Was wonding if set-back boxes would give more leverage to keep the hull on plane with negative trim, plus maybe put the props in cleaner water(?)

Down the road I am looking at major engine mods and I would think set-back boxes would benefit even more.

Anyone have before-after experience on twin-stepped, deep V hulls (big or small blocks)?

Putting the boxes on will put more weight farther back and create more bow lift and the need for more tab to maintain lower speeds.
I would try some 5 blade props for what you want to accomplish.

ask this in the formula owners section