If wondering if somebody could help me to resolve my concern .. I have stock 600sci not stage running 5 blade maximus with xr upper and ssm bottom i brake the drive second time this summer first with the boat asking myself if i go to imco scx if yes could i keed my bottom and only buy the conversion kit or install cooler on the xr ?? I run 78 in GOOD condition with 29 fountain 2011 ???!!!

And i figure to put the wipple upgrade to run in the mid 80 .. Doninhave to change prop ?? Scx gonna hold it reliable??

SCX would definitely be an upgrade. If you are running a shorty that may be part of your issue. I have a friend with the same boat, he broke a drive a year until he put the standard length lower back on it.

X dimension was already high from the factory to maximize speed and now you have made it even higher and are running Maximus wheels which is additional strain on the drivetrain

I'd say one of my questions would be- only 78 with a 600? I run 81 with a 575.

As far as the drive, you really have to baby them out of the hole. It's also a lot of boat for one out drive (weight)

What part of the drive are you breaking?

[ATTACH=CONFIG]543617[/ATTACH] @740hp 100+mph IMCO SCX4 5 blade merc cnc cleaver

My brothers 29 Fountain with 525 ran close to 80 with standard length lower. It had a high X-dimension, making it hard to plane out.

I'd go with the SCX top and bottom , run the Maximus , but you will lose about 4-5mph top speed ...that's because the gear case is
substantially larger . Trade-off is you won't brake drives on a regular basis ...

They made shorties, so they can sell more spacers... That's the joke around our buds!

Your breaking the drive because of the 5 blade prop...
I would also look into a DriveGuardian