I talked to Dave today.It was his opinion that if you use an ace drive with the extension box your x demension stays the same.The standard is longer and would require raising the engine to get the same x as before.He thought depending on where you start it's a good time to change if needed.

I guess my real question is after looking over as much info as i could on several drives, I still am not sure which is the right drive for me. I will be making 1150hp on race gas with raised boost and I want to be able to do over 110 mph. My Fear is going with a drive setup and not getting it to perform to atleast 110mph or holding together. I've seen a 260 with my almost same engine with a Xr drive and imco lower do 113mph on a radar run, but breaking at that speed, is not a option. I currently have the hull stripped, so If I'm going to modify the stern and have to glass anything up now is the time to do it. Whats a drive thats going to preform, hold together, and not cost me the family farm ? is Konrad, Bmax, #6, #3 or Arneson the way to go ? Anyone with experience please chime in.

At the speed you're targeting, set-up and balance is absolutely critical for your hull and the drive needs to be a part of that equation. Your best bet is to talk to the factory about your goals, listen carefully to what has been tried before and proceed from there.

With that kind of power , you might be better off with a speedmaster .Older style wet sump 6 might be the more reasonable way to go .Ask the factory if they have any information on any others rigged this way,and do they think you need a box.They should be able to give you a good starting point for the x factor.Note with a speedmasters you can add spacers to the drives to adjust the height .Good luck with your set up

Only problem is a #6 is a monster drive..... Thats alot of weight, you have to move the engine and drive location and use a tranny and stand off box. Its another trick getting the X factor set back up also..

I'm not sure that there are that many single engine boats that have been successfully converted from Bravo to Arneson? There was a lot of talk about converting a 30’ Superboat last year and the result was that the boat should be built from the start for the surface drive with no notch in the transom. The Arneson Bravo conversion kit was not going to have the prop low enough in the water.
Twins engine boats converted from Bravo to Arneson surface drive, Yes.
If you have the $$ then a Konrad Ace with the tranny in the extension box would be a good way to go. The only thing is that I don't thing they will warranty over 800ftlbs of torque.
For the $$ for the Konrad, you could have 2-3 spare Bravo type drives.