I have seen those broke as well.

Would be nice but I heard they don't work to well with the raised center pod single engine cat, not sure.

Just rode on a T/S w some of these a few weeks ago. Can we say ROOOOST!!!

I doubt the loss of speed is any worse than going from Bravo to #6. Most of those boats have slowed down if no power was added in my experience.

I debated for a long time what to do when I kept breaking drives. In the end w 725 hp a side I decided to spend the money and went w SCX upper and lower and now I go boating every weekend. My story w my boat is very long but in the end I wanted reliability and Im happy w my decision. Sorry this isnt the answer to the OP question just my 2 cts

I have the SCX upper with the SC lowers and made sure the drive height was the exact same as the Xr's were set up so as to not be chasing a new x dimension, etc. Yes, I did loose 3-5mph on the top end. I run 700hp through them and other than a cone clutch sticking in one, they have been bulletproof for 6+ years. When I bumped the motors up from 575's to 700, I blew three Xr drives in a year and1/2. I was considering putting the SCX lowers on but the boat runs so well the way it is set up now, i don't want to screw with it. I think many people think the SCX-4 is going to be amazing but remember it will change your whole drive set up, height, and running angle. Most guys I know who did it had to add spacers to put it back down in the water.

The SCX upper seems to work great, it's the SCX lower that in my opinion needs help. The bulbous design doesn't cut through the water anything like the SC. In our application with the standard 2 inch short SCX the boat would constantly wander and not want to make turns, with the 2 inch spacer it acted like a giant Dipsey diver.

I don't know why but I have heard that the SCX upper and SC lower seem to work well on 25 Daytona's but not 26 DCB's.

Bayliners, LOL.
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