Jamie,
There are to many variables to say when, but the more power, the heavier the boat, the more air it sees, and the more the drives get beat on (coming out of the hole, hard acceleration, etc), the faster they will go. The teeth on the upper ring gear is typically the mode of failure. It starts with wear, but they often shear off.

In Franks case, I'd be surprised if those drives made it past 50 hours with 800 hp in front of them in that 42.

John I talked with you the other day thanks for all your help! Question for you, do you need a helmet change with your drive? Also can I bolt my XR lower to your upper? I am still looking for the best and most economical solution.

That's a lot of Fridays!

Drives only seem to blow sat-sun so you don't have to worry

You can do that and you will probably lose 2-3 mph over the stock -2 sportmaster. Please correct me if I'm wrong. The ASD will give you a speed increase that can be quite expensive to match if you want to have that with a Bmax or SCX drive. Ie. much bigger hp motors.

Don't take this as a personal attack on the Bmax drive, it just my way of looking at it. There is no doubt that it has its place in some setups. Imo, this is just one where I see the Arneson as being the better choice.

What is the price of speed and reliablility?

As far as speed lose, in the old Bmax you had a choice of well lets just say 1.3 ratio and folks would put them on thier boat coming from a 1.5 ratio and lose 8-10 mph and blamed it on the lower housing. As with any new drive set up props will have to be tested to get it dialed in.
Back in the early 2000's one of the boating magazines did tests on all the lowers and the Bmax lower was the fastest at that time. I don't have the article but I'm sure one of the members on the forum will. Today the Bmax comes in a 1.5 ratio as well.
Rik made a statement that starting with a blank slate that Arneson is a cheaper choice and I was looking for a how he figures that.
A.O. Razor I would like to know what Bmax's, Imco's, Max Machine and # 6 drives you have had and on what boats and what power. And then the boats you have had with Arneson's that make you a expert on every thread that comes up. Maybe if you have time we can talk and I can gain some in site for when we come out with new products. It is hard to find someone with your knowledge in the marine industry and I would like to hear your experience's.

No helmet change is needed but with big power I would change your gimbal ring to the Imco HD.

You will need to change the vertical shaft in your lower to a Bmax shaft.

Yes I understand the variables, and the airing it out and acceleration of the big boat fall under the decent driver/throttling. I was just trying to see if anyone had something somewhat close and how long the gearset lasted in there application. I think frank would be ok with changing the fluid every 20 hours and planning on the uppers needing to be gone through at 50 since he puts 40 or so hours on a season. That would pretty much get him through this season and let the piggy bank recover for a full drive upgrade next spring

You guys should know by now I'll take the chances on the cheap way out! I put used bravos on an 11000lb boat with 600 hp lol

I have HP gimbal assemblies and essentially all I had to do was take out the 4 upper studs on the helmet and bolt the drives on. My drives were delievered via UPS, I got home from work at 5:30 pm and had them installed before dinner. After dinner I went to the store to buy some bolts for the steering, drilled the holes in the wing plates and installed my steering system. I had enough adjustment in my steering tie-bar from my Latham setup to use all my existing parts.

The directions suggest adjusting the steering for full-swing but in my case I didn't have to move anything.

I've had my BMax HT's since 2006. I ran the ocean most of those years. I lost 2 mph installing the drives then a few years later in 2009 I raised my X Dimension and picked up 5 mph on top. In hindsight, when I ordered the drives, I should have bought shorties and I would have picked up speed from day one. They also didn't have the 1.5 ratio back then so I wouldn't have needed to buy new props if I bought the drives today. :)
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