I have a 31 sutphen im working with has prop shaft 6 3/4 below bottom of the boat with standard bravos now what are others running on there straight v hulls. Im going with 12'' extension boxes and -2 lowers now is my opportunity to move the x up since everything is coming off the transom anyway.

Looking for tried and true instead of theory here.

Mine are 9" below the bottom, no steps but the transom has a notch. Boat runs 58. Not sure if that helps or not. I actually added 1.5" spacers to bring them down because I couldn't get any bow lift out of the trim before I added them.

Twin engine sutphens run pretty well with them a little deeper than most other straight vee hulls. I've noticed they run real high out of the water, the lifting strakes pop them way up. If I get a chance a customer has the old f2 race boat, with bravos on boxes I can measure the propshaft height next time I see it.

finishline: is she BBC or SBC and IMO what your doing is changing the X __ what year is she and tell us about your power, gear and wheels. __ Did you ask Ritchie by chance? He prob. has the best tried and true answer for you.

I think the F2 31" Sutphen 2..25 below bottom on 12" setback.
Steve

1991 31'. twin bbc 36" center on the drive centers 500hp each side. Bravo one drives 6 3/4 deep 27-28p b1 props. This is my current set up as it sits right now. I will be going to a standard 12" box and -2 imco sc drives.