Thx, Peachy! I am not the first to convert one of these to electric, but AFAIK first to use a 1100kv 5698 motor.
Some progress today: Machined up rough shape of strut. It is cut from 6061 alu. Machines well. I used a 12 inch miter saw to cut the 6x6 sheet down to a 3x2 block, and then machined this down to rough dimensions. Waiting on stainless bore and flange bearings from chinabay. 1/4id 3/8th od. 10 for 10$ or something like that. Also found some nice stainless thrust bearings for the 8mm motor shaft and for the strut. So all forces that I can account for radially and axially along the prop shaft at strut and motor have been dealt with. My only issue is that the flex shaft housing is flexible nylon/teflon (which will be deflecting all over the place at 70 mph). I may be able to slip the 1/4 brass shaft housing through this as the new one is a bit smaller than the original shaft and teflon liner.
The most critical part of the strut is making the bore correct diameter and parallel to the strut.
As for props: I have a 1/4 bore 70 x 1.6 3 blade and for fun, a four blade 67 x 1.7! I know 4 blade is not the best at high speed, but fun to experiment. The original gas prop is 79 x 1.4 2 blade. But it does not turn anywhere near 30,000 rpm, which is about where I am aiming for with the smaller props!
More on props: Interestingly, it would seem that with a counter-rotating prop, and with the lower half in the water, prop walk would direct the stern to port, and thereby directing the bow to starboard (right turn). So why is the rudder on the right? Well, it must be countered by the turn fin, placed on port side (which this model does not have) So do I add the turn fin? I guess I would if I only wanted to turn to the left.... I was actually considering using MHZ 1 into 2 transmission to drive 2 smaller counter rotating props and using a centered single rudder.... I was also considering using a twin rudder set-up, but the less drag the better. I watched a few videos of this hydro with the high mounted 26cc gas engine. She still held a pretty straight course, but leaned a bit in the turns. Of course, I suspect gas engine speeds did not exceed 50 mph.
Also, got a holux gps tracker for cheap. tested it in my car, works great, and easy to use. It is about 3x2 inches. plan to tuck it into the hydro and test speed with different set-ups...nothing new for fast electric, but now prices have come down on all the parts for this build, so time to test.