MRP Miss Budweiser Setup

[JLG627]

I have a vintage MRP Miss Budweiser with two 8 turn quad brushed r/c car motors geared 1:1 to a single shaft. I need some good prop size recommendations for this setup. The stock plastic prop that is included in the kit is only 31mm in diameter and the only recommendations I can find for twin motor setups like this is for a gear ratio of 2:1 and they're recommending Octura X447, X447/3, X645, X646, X646/3 props. How much smaller a prop do I need to go with for a 1:1 gear ratio and a motor setup like I've got? Do I need to invest in something like the Hughey dual motor mount/gear reduction setup or can I keep the factory setup I've got? If anybody out there can help me with this, I would be eternally grateful because this has been a real headache!!!

[Scott T]

Those are pretty hot (high revving) motors for a boat. I assume 6 cells or 2S lipo per motor? The original Miss Bud had 12 cell voltage to each motor, which would fry the life out of 8 turn motors.

I would stick to the small size, something like an X430 or X432. I just don't think those motors would handle any bigger props. Let them rev.

The other option would be to drop to higher turn motors, so you can swing bigger props. Or keep the motors and find some gears to allow you to run a 2:1 ratio.

[eboat]

I had one of those boats last season
In the end I took out the gear drive and the solid shaft and put one motor and a flex shaft in it
I think the main reason they had the gear drive was so they could get the shaft closer to the bottom of the hull to keep the angle close to flat out the back of the boat
I do not know about the motors you have but when I put the one motor in instead of the 2 factory motors it was twice as fast with the one than it was with the two
With the flex shaft you will be able to adjust the angle of the prop

If I had it to do again I would just put a SV 27 motor and esc in it

[Kramerr]

I have the same kit. I was thinking on selling mine, but reading through some forums, I am probably going to remove the original motor setup and put something with a bit more power in it. Any suggestions ???

[Fluid]

As stated above, those are very hot motors for that boat, a melt down is iminent. It came with 12-turn motors of old designs, not at all like more recent 05 brushed motors. The easiest mod is to series wire the motors, this will put half the pack voltage through each motor. Example, if you are tunning 12 nickel cells, wire the -lead from the ESC to the - of the first motor, connect the + of the first to the - of the second, then the + of the second to the ESC. Each motor will now see half the pack voltage but full amps. The motors originally came parallel wired so that each motor saw full pack voltage but half the total amperage. You will need to be conservative on prop choice, I'd not go over an x435 without testing.

Really, these hulls were designed for 25-35 mph and didn't handle much more speed very well. The plastic was brittle 20 years ago and the additional time has not made it stronger. If you insist on using it, toss the 05 motors and put in a single direct drive limited motor like the ProBoat 1800. Keep the solid shaft if you want but a flex cable will be much better.




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