whirlwind, We had 1.35:1 Max uppers and lowers.

Strip,I'm looking for 5200rpm max.

Are there any other choices beside the B-Max that would be an easy swap...IMCO?

I'm hearing IMCO has a new shiftable drive but I haven't seen them on any boats or have any real world results as of yet... I'd wait a few years unless you have the dinero..

That could be why the Max Drives didn't hold up... I've learned that the bravo's need lots of RPMs to last...

I understand the thery behind more rpm is better, but common. If you have 700+ hp infront of a bravo drive, its more about the man on the stick then whether your turning 5200 or 5700 rpm.

Not necessarily....I'd say it's somewhere in between. :grinser010:

Every IMCO Extreme SC that blew up on me was @ 3600 rpm in dead flat water... Since the boat was propped for 5200 rpms there was more torque load on the drive at cruise speed than if it was propped for 5700 etc. The weight of the boat is also a big contributing factor.

A good 70-80% of bravo failures happen at cruise speed, just aske mercury or any of the guys who are in the know.

When we had the Max Machine bravo's they failed at 3000 rpm's. The engine builder wants the rpm's set at a max of 5200rpm's to make them last and because they are large cubes-678ci.

Me too.

I run a @4200 lb 27'er with a 600hp 540 twisting the old TRS setup with a huber trans. The huber finally just let go and I'm trying to rule out a bravo conversion - I do my own mechanical and glasswork so the bravo xr is my cheapest option, as opposed to the Konrad, when all is said and done. So far, it seems that with the bravo I could stay near 600+hp and get the speed I want (3-5mph more than now), or go Konrad for absolute reliability but would need to go at least 700hp for the same speed.

I'm sure the bravo would do ok if not for the water conditions I often see. The chesapeake bay gets wind waves that are large enough, and stay close enough together, that when running fast on top of them, the prop will grab air without the hull lifting or any kind of warning - so drive preservation with the throttle hand is impossible - you always get a few "slip and bite"s, which kills an unbalanced combo such as mine. After watching the bravo aftermarket for 15 years, I don't see any huge strides in dependablity there either - if there was, these conversations would probably not exist.........:)

A local shop near me is riggin a lot of conrad conversions with great success.They warranty up to 800hp .Direct replacement for trs, or extension boxes for trannies with bravo boats .Bustin drives is no fun!!