What did you find? These threads are more interesting to me than any who done it mystery.

My flanges are not parallel, which is unfortunate because its a lot of work to make it right. The community of high performance boaters is awesome, thanks for all the tech advice everyone!

There is another way besides parallel, if it would save some work. If you can split the angle exactly so the input flange to shaft is equal and opposite the shaft to output, it will work too. Just takes a little more math

Also, you have some range of adjustment vertically in the extension box. They are normally set up on the lowest of three settings. If you needed the box to go up to match the engines, you could do that very easily, and then add spacers if you needed the same propshaft height, or just go faster if you don't. If the engine is already below the input flange, then that's no help.

Double-check your hatch clearances and check the implications on the exhaust before doing anything...

Also, I've wondered about seeing if someone could make up a CV-type shaft to fit the Spicer flanges. That would cure that problem.

T, Moving the box won't help - it will change the total angle but not change the face/face angle. It is possible to make a box with an angle built in to compensate.

Yes the intersecting angles will work almost as good. I have done it by making some flanges with equal length pointers on them then moving things around until they touch at the tips.

I was all set to try a cv back in the 80's ( I had bougt all the pieces) when someone pointed out that Arneson did not have any luck with them and went back to U joints.

Coming back to this guy's......... I may have been confused earlier when I was reading through this. After rereading this it sounds like I can be slightly offset either side to side, or up and down, as long as the two faces are square to eachother. If thats the case I think I am actually still good? I am thinking that I may pull the boxes and put a thin spacer between them and the boat, as under load I may be pushing on the bearings as I had the slip yoke almost..........bottomed out to fit the driveshaft between the two faces.

Also any ideas on were parts can be had for these boxes, or anyone you rebuilds them? Marc do you guy's get into those? Thanks for all the advice so far!!!

Anymore input here, trying to come up with a game plan?

yes it is best if the flange faces are parallel and offset up, down or to the sides a little.

Okay great, any thoughts on parts or who rebuilds them? I have called speedmasters in fl about 4 times no one ever answers, or returned my messages? Does anyone have a # for Marc at Bam, can't seem to find a good number for him?

I remember chatting with my buddy Rob about this a while ago so while greasing my drive shafts yesterday I looked and sure enough its the same setup. Extension box fluid change! LOL it never ends with these boats!

Interested in adding a fluid reservoir to monitor the level. How would I go about that? How much fluid does it hold normally? How do you currently change the fluid? How much fluid would you use if you added a reservoir? Can you overfill it?

The stellings boxes on my last boat just had a grease fitting there.

Thanks!