Call Dean at the B-Max and he will tell you what to do. If the B-Max can not handle your engine then the #6 is the next step. I personaly think B-Max is the answer.

Clueless
I have a friend who has a full season on a B-Max with 1300
plus hp ,this year he is trying for 1600. Sat. is dyno day for the
monster

When you bought the drive from Imco did you tell them the HP you would be pushing through it? 900hp/tq is huge and would think Imco might steer you away. I know they do not offer warranty. It seems awfully expensive to "try" the same thing 3 times.

I know of a Carrera 257 on Lake Norman, NC with 1300 HP and 1200 ft/# that torched 9 bravo's in 2000. Went with the B-Max last season..no problems.

A big factor often left unsaid is boat size and weight relative to drive life. I know it's an exaggerated length Fountain but it still has considerable wt and wetted surface area, especially for that power.

I suspect the first two imcos were not the "SC Advantage" that you have now with the new beefier upper housing, pinion support and the XR gears. That drive should be a significant improvement over what you had but may not be enough.

If it's only got 5 hrs I would sell the upper and run the Bmax upper- huge difference in torque capacity, size of gears etc. Talk to Dean maybe you can swap uppers, keep your lower etc. Good luck!