Why don't you ever see extension boxes on the fast (120+), stepped vees???
 

You see a lot of boxes on older straight bottom stuff but never on the bigger, stepped, #6 boats. Why is that??

Compared to the hull bottom (running surface) they are already raised and set-back ?????

BTW: that's a guess from me as many boats with steps, after each step (going torwards the transom) the hull raises.

Looking forward to the real answer.

43' outerlimits on long island has a drive box don't no how much it did for performance. But I thing it runs better than the sister boat handling wise.

The reason I am asking is because I can't recall ever seeing a newer 1075/6 or 1350/8 setup with boxes from the factory. Just wondering the real answer, as I am sure if there were gains to be had, the new boats would be rigged with them.

I am re-rigging my boat with different drives and Im loosing about 8" of setback. I am wondering if it is worth adding setback to get back where my #6's on 12" boxes used to be or leave it alone.

Remember, extension boxes (or setback on an outboard) is designed to give the drive more leverage to lift the bow. Lifting the bow on a non-stepped V-bottom was about the only way to reduce the wetted surface area, and thus drag, to increase speed. Steps changed that by lubricating the bottom with air bubbles. Doing this eliminated the need for excessive trim to gain speed. So a step bottom generally doesn't need much leverage to lift the bow. Of course the tiny bubbles created as many problems as they solved. Just ask Dean Martin.

One other thing more of a PIA when rigging the boat long drive shafts needs a two piece shaft to eliminate whip. Think it would be better all around with a box handling wise.

I had rerigged the drives on my OL as 14 apache had stated. It was a great advantage for me, for many reasons. I think the reason most boat manufactures don't install them is the cost vs the gain that they may see. I have bin amazed at the way most boat manufactures give there boats to there customers the set ups are horrible. I would put boxes on the boat the benifts outway the negitives.

The cost part of it is crazy to me as it is almost negligible on a $500k-$1M boat. What did you gain when put the boxes on?

Reggie Fountain was asked the question... His answer was " if they would run better with them, we would have installed them" he said that they look for every bit of advantage, but if a boat needed a box, they should have that all figured out before they made the mold. That being said, its not to say on some boats manufactured... boxes don't help. But the companies that cared mostly about speed would have designed it into there mold like Reggie said.

Statement 42V's have extension boxes on there boats.