999JAY

Another thing to consider all these gears in the gearbox, overdrive box and drive are going to rob power even dry sumped you could easily be loseing 10%.or more.

BigSilverCat

We did look at making the standoff box into the overdrive box, just like everything there is good and bad about both. Without cutting a bigger hole in the transom (again), it would move the drive back a little farther which is good and bad. The standoff boxes were 5200 glued to the transom so it will rip fiberglass to get them off which would require glass work and paint to fix, the drive shaft would have to be shortened , hydraulic steering and trim lines would have to be redone, would be more difficult to open up to inspect or change gears, ect. The biggest problem would be that if something happens to the overdrive/standoff box it could not be bypassed as easily.

The good would be the Standoff boxes are over built and could be lightened enough to almost make up the difference of weight of the gears inside them so it would be about the same overall boat weight, keeps from having to add more transmission/motor mounts that I will have to add from adding the overdrive box and moving trans back.

By mounting the overdrive box to the bell housing there are more benefits, We designed the overdrive box to have an offset in the side/side and up/down directions to make up most of the offset the drive shaft was making so we will not have to move the engine over or forward to keep the correct alignment, the transmission electrical shifting and cooler lines will reach moving it back to not have to change them.I could use the overdrive with different drive options, I will have another set of drive shafts made instead of shortening these and if there is a problem with overdrive box just pull it and put trans back where it was with the longer driveshaft. We may end up with totally different engines at some point that have a different rpm range and I could pull the overdrive box out easier. We will not have to worry as much about water intrusion or not seeing an oil leak, ect.

outonsafari

quote- By mounting the overdrive box to the bell housing there are more benefits, We designed the overdrive box to have an offset in the side/side and up/down directions to make up most of the offset the drive shaft was making so we will not have to move the engine over or forward to keep the correct alignment,

twice you've mentioned this, if i'm understanding it, it means a left and right side overdrive box / transmission, right ?

BigSilverCat

Yes, there will be a left and right that are different, but it will only be the case that's different. All the other parts will be the same, gears ,shafts, bearings, seals, ect. When we're machining the case it will be a couple different programs and setups but will not take much longer to make.

IGetWet

What was the problem with the arnesons again? I'd go back and try to find it but I'm too lazy and that could take days. And by then you'd be onto installing the helicopter pad on the front of this thing and I'd be way behind.

BigSilverCat

The biggest problem with the arnesons was not being able to keep them straight. You cannot use a tie bar because it would drag in the water coming through the tunnel and if you build a big stand up high it puts too much leverage on the trim ram and bends it. I made several parts just to be able to see how straight they were and had a trim pump inline to be able to spread them apart but when I would floor it they would start pulling together. I think the fluid was leaking past the seals. There are several things I could have tried to be able to keep them straight but it would still leave some questions about how to set it up where we know how to set up a 46 skater with number 8's to not have to do a lot of testing to get the sweet spot.

IGetWet

Gotchya. I'm surprised there wasn't an easier solution to the arnesons. I would've thought they'd ran into similar issues on other skaters or big cats for that matter and that there's enough of them running arnesons to have a better starting point.

What's the difference maintenance wise between the M8s and the arnesons? Will you be servicing the drives at some point during the big trip?

999JAY

That's strange I have run in a diesel 46 Skater with Arnesons without any problems drives performed flawlessly.

When I was there in NJ I had the privilege of seeing JetSet another Skater running Arnesons with 1800hp turbines a side no tie bar and no issues.

Sounds like the seals in the steering ram might have be at fault or the seal assembly needed updating.

A couple of examples of big power Skaters ruining Arneson without tie bars, #8s will certainly help trim the boat better sub 100 mph.

999JAY

These are a nice option for a overdrive box, problem being they probably have to much offset for your application with the #8s.

999JAY

Tyson if you ever decide to go back to the Arneson concept I wouldn't mind developing a external 6" drop 2 speed drop box with interchangeable gears that will accept the Arneson/BPM tube and trust ball.

As far as I'm aware this is something that hasn't been done yet and would certainly benefit diesel applications,
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