up for conversation , would you use a extension box or ITS boxes ? and WHY ? reason is I am looking for some more speed . currently running a twin step gun with xr drives and 2 in shorty lowers .
talked to carter and he said not always going to be the best option . I have another gun in the storage unit next to me with ITS and 6 in boxes and its fast and works great .

The zeiger boxes are designed to set back the factory ITS system, however keep in mind for every 12 inches of set back you lower your prop center line by 1 inch. Factory its is 8 inches and the zeiger box is 5 i believe.

Dang, ITS assembly on a 12" box. Those *****es would be hangin off the back like the monkey on Hillaries back!

Has anybody installed boxes and gained or lost any performance ?
because I am thinking of re working the power in the boat and drives. because I love the boat but I want 95-100 mph

Don't quote me, but I'm not sure anyone who has added boxes gained speed. I believe the boxes boxes gave the
drives more leverage on the boat, possibly making it run better in rough water.

I am adding a 12 inch neutral box to my Daytona 26 this spring. From what I have been told that a box always helps a cat. Yes they do allow the drive to lift the bow easier - that means less trim. It may also allow a higher X dimension and that makes the boat more efficient thus more speed.

26 sutphen, 2 seat race boat no cabin, was a death trap reportedly with a box, no matter what drive height they used. Box removed handles very well and won multiple races. Kinda apples and oranges but an application where the box wasn't working out.