I talked to Rick at IMCO. He was very helpful and told me very candidly for my set up not to run SCX lowers due to transom lift. My hull does not like it. He said that they have been unsuccessful yet on a hydrodynamic redesign. I'm sure they will get there.

Damnit man! All the Drive parts I have bought in 2 yrs paid for 1 side.
Hind sight We all know what good that is.

On a tech side What if you have boxes already? Do they go away?
and post that vid of the T/S again! I think that may push me some more.

I think you know what that letter to Santa needs to have on it this year!

KAP told me he lost 8 mph with the SCX upper/SC lower combo... which is the greatest speed loss I have seen so far on a single engine application.
There was a guy with twins that initially reported a 12 mph loss, but then put shortie lowers on and re-proped, and got to within 3 mph of his original speed.

This is with using SC lowers.
I have not followed or studied cases where a Bravo or SC drive was replaced with a SCX upper and SCX lower.

I also know of several cases where there has been no speed loss with the addition of the SCX upper.

John Lamont had a Nordic Thor, and went from a Bravo XR upper, with a Sportsmaster lower, to a SCX upper and SC lower, and picked up 1-1.5 mph.

I think it depends on the hull and the setup.

Chris

Any single engines boats do this conversion? Does the motor need to be lowered, or notch filled in?

This one of the 39' in Turkey? http://www.youtube.com/watch?v=gWTKf0FSO7w

Or the 38 in Russia http://www.youtube.com/watch?v=b7uwQHK9NUc

You remove all the Bravo stuff including the boxes as our boxes are made to fit the Arnesons.

JRider:

You cannot fit a 2 inch prop shaft on a XR case it will not fit. the only interchanging props that I'm aware of are the Maximus on NXT prop shafts.

Yup I broke a tooth off the pinion gear on the SC lower.

The full SCX both upper and lower cost me 14-15MPH on the top end to much drag in my opinion. The combo is very strong but damn too much top end loss to justify it in my opinion.

A. Surface Drive X on our boat ran 123 MPH, acceleration was mind blowing.

B. MMX i.e... built IMCO ran 121MPH

C. SCX/SC lower ran 113MPH...best speed ever for my boat with this combo...drive height set at standard length. Speed loss is 8 MPH.

D. SCX/SCX with cleaver best speed 104MPH on a very hot day...not really a fair comparison.

NOTE: The acceleration in the mid-range is kick azz but top end feels like an anchor is dragging. The drive needed to go up about another inch but cannot due to clearance issues.

Caveat on single engine cats mod V-P hulls going to a surface drive is not an easy proposition and can be very costly just in propeller costs. I won't even mention the time and effort required to dial a particular hull. As it is a very small window to tune a boat and you can easily blow past the sweet spot.

I want to try a one inch shorty lower either a IMCO SC or a Max Machine Billet lower -2 spaced down and see if I get my speed back on the SCX/SC combo.

According to Chris C-BLR--- he says it is the ticket and I trust his data and recommendation. If I get within one or two MPH of my B exemplar above I am done with drive combos.

I will keep the standard lower for a quick backup on long trips.

KAP

Sorry for the hi-jack. Just a quick question for Rik,is there a lose of top-end with the Bravo conversion?

No, typical is (with twins) 10-15 mid range increase and 10+ on top end increase also.

Rik, your drives give me a woody, so hot, me want.:drink: