that is the most in-expensive way to do it. It just may be more work in the engine compartment to re-rig everything to come up that 3". Also do you have enough clearance in the engine compartment to come up 3" without the air cleaners hitting ?
Don

Good points just thinking of options.

Just bolt whatevers cheaper back there and Ill adjust it with my killdozer

That might work!

What i am saying ,is even with a -3 IMCO box you actually only went up 2" !
Plus the rerigg with the engine(s) is not worth it because now you change your center of gravity ,which then you may need a diffrent X-dimension ?!
A used stelling box is around 1500 + driveshaft 2-400 cupler for flywheel 100 , so at the most you are looking at 2K for box setup + shorty used 1500-2500 .
So around 4 K and be done with it.
Motor mount change , IMCO box ,torsionshaft to puton bravo + messing up the boathandling and start over with dialing in,maybe now need a shorty or a spacer !?
Is that worth it ???????
If you go with stellings , i think it makes it alot easyer and probable cheaper in the end, because you can play around with your X-dim. without messing with the Motor(s) .
Its a fact ! ,sorry !

this is what i did with my AVS and picked up about 6 to 7mph at cruise and 5mph on top end also the handling difference was greatly improved like driving a who different boat

ScarabJ
How long is your Scarab? I have a 98 38' Scarab non-stepped hull with motors putting out about 700 HP. I put on Imco 2" shorties because the X-Dimension was really low on this boat. It definitely helped out. I am thinking about adding stand off boxes this winter and going up another 1 to 2 inches. That will depend on handling and speed of course.

1999 33 avs

I have a non-stepped hull...also NO notched transom. My 1990 Active Thunder was originally built with TRS drives. I wanted to upgrade/modify the boat to Bravo One XR drives and while I was at it I thought I would add the Stellings extension boxes. I contacted the boat manufacturer for suggestions and they told me to mount the boxes as high as I could (just below the rub rail).

The centerline of the propshaft nut sits about 3.5-4" below the bottom the hull (directly in front of the drive) at nuetral trim----this is with a completely stock length (no nosecone) Merc Bravo One lower gear case. I used a 4-bladed 32" Bravo prop.

I wanted to experiment with some IMCO -2" shorty lowers. I didn't like it at first because the 4-bladed props were extremely poor in getting the boat on plane until I bought some Hydro P5X 30" 5-bladed props and solved the problem. However, my boat is now about 5mph or so slower in the midrange cruising speeds, but I gained about 5-7mph on the top end. The really nice thing about my current set-up is that I love how the boat handles and rides on top of the water much better. It drives and rides like a totally different boat on the positive side.

Perhaps if I try some 32" 5-blades vs the 30's I now have it may give all of my midrange cruising speeds back which I would really like---but not sure if my boat can spin a 32" 5-blade at an RPM level I would like to see.

Lotta good info here about boxes. Daredevil certainly knows his stuff, and makes a good case for the Stellings.

When I upgraded two years ago, I looked at all the options to get a box and a raised x on my single. ITS+shorty, Stellings, and Imco -3" box were the options. I chose the latter based on the argument that keeping the coupler and trasmitting through a torsional shaft was good for the drive (but canīt verify if it helps significantly).

So I bit the bullet and went for the Imco, keeping to a stock DWP XR drive, as I had been told that in my speed range (75 -80 mph) the standard drive would be faster than anything more exotic (shorty, bullet nosed lower, low water pickup).

The 3" raised motor has not in any way had a negative effect on the handling. In fact the boat is night and day better than the stock version, and ran 80 mph with 525 EFi power. Incidently the motor has actually moved back a tad, as it moved 3" up the 12° angled transom.
In my opinion, one of the speed bringing aspects of a box, is that the c.of g. is moved rearward, whilst the drive acts like a third leg stabilising the boat as the hull start to air out.

Another advantage is great access to the motor and bilge area.

The Imco box has generous hatches on both sides and plenty of space inside for installation and checking transom assembly connections.