It's so good Jesus turned it into wine.

My motor is mpi 509 m3 SC 730 hp

Panther, what do you mean by prop as high as you can?

Your drive is blowing up because it is either set up wrong, poor oil quality or the new XR gears are failure prone as is claimed by many. I too have a 27 foot Baja except I have 350 hp more than you do, I used the max worx upgrades in my drive and assembled it myself, including the same xr upper gears you are running except my upper gears are going on 8 years old. I ran 700-750 hp for 2 years on them, 950 hp for 3 years and now have ran my 1050 hp set-up with a little time with my 1115 hp pulley going on its 3rd year this season. I have more than 300 hours on my upper gear set and I think it might be closer to 350 hours. I run a 30 pitch labbed prop and can easily turn it to 6200 rpms, I have spun a 32 labbed to 6000 also. I am not saying I haven't broken parts or been in my drive, I just haven't broken or chewed up the upper gears since 2004. I tear it down every 20-30 hours and inspect it, I drain the oil every 10-15 hours or at least I was before switching to a external oil pump with a cooler and filter last season. I holeshot my boat after I get it moving and drive it like a drag boat sometimes so I am not that easy on it by any means either. I have entertained the thought of a B-max but uppers has never been the problem on my boat, it has always been lower gears and as far as I know they still use a bravo lower gear. My lower 1.50 ratio gears would last 50-100 hours before they would start coming apart when I had 700-750 hp, when I went up to 950 hp this dropped down to 10-15 hours. I experimented with various heat treating, dlc coatings , cryo finishing and iso rem polishing of the lower gears. Between the cryo and iso treatment and getting away from the garbage royal purple I was using to something better I was able to get closer to 40-60 hours out of a lower gear set and that is at my current power level-1050-1100 hp.
I am definately going to try the NEO oil , I love these drive threads and the new info that comes out, Smitty

I used royal purple when I was experimenting with different things on the lower gears as mentioned in my previous post-heat treating, dlc coating, cryo, iso rem and when I finally quit using it and switched to something better (amsoil severe gear w/lucas additive mixed in) my lower gear life doubled, I think Royal purple gear oil is GARBAGE!

Turn as many rpms as you safely can with your engine if you're running big power thru a bravo drive. It can't handle the torque, especially at 4-5000 rpms where most drives tend to blow up. (near peak torque in most engines.)

I've learned the hard way over the years... But now I've been running the BMax since 2007 with much less maintenance or issues than a Bravo.

What does a 5 gallon pail of the this new oil cost?

It's $100 a gallon, and it smells horrid- so you know it's gotta be good, lol.

Who makes it?