Engine upgrade to Miss Bud 1/12

[Eytan1958]

All is running OK with this boat.
I have changed the prop to Y535 which is nice.
My only concern is top speed.
I want more speed on this boat.
Anyone with some upgrade to a stronger motor and a bigger prop?
Anyone tried the OS MAX-21RG-MX? :D

[Hydro Junkie]

Don't know if it would be advisable to put a 21 in that hull. Those Buds are layed up VERY LIGHTLY and may not handle that kind of power. I know some of the guys running the gas Buds are having trouble with the Zen 260's splitting the seams due to the torque from the larger engines :( You might be better off building or buying a Sport 40 hull and drop in a 45 with a tuned pipe. With the exception of the outriggers, the Sport 40's are some of the fastest boats on the water :cool: If you want to go this route, you could get plans for a boat from newtonmarine.com and shrink them down to three foot. You would have a more stable hull for the power you are talking and a faster boat :) After all, isn't speed what we all are after? :D

[BoatDoc]

after doing a mild port job and shortening the pipe a little in mine, i was getting a good increase in speed. it came at a cost though...stress cracks everywhere!! any additional power requires beefing up that fragile hull.

[Hydro Junkie]

Wait a minute!!!! The Doc and I actually agree :eek: I was under the impression the gas boat was the one with the hull problems. Guess RCBM should do another review of the Pro Boat Miss Dudweisers, using the input to these forums as a guide :(

[riche]

Hey boatdoc,

how much did you shorten the pipe?
I heard as that 1 inch shows good results.
but they told me to take as much of the inch from the header.
Is that close to what you did?

[BoatDoc]

i only shortened it about 1/4 of an inch. i didn't get much time with it after that due to a "sudden stop" involving some big rocks. she'll be back in action one of these days for more running, but i'll probably have a MAC pipe on it. i don't recommend going all the way to 1 inch right away. shorten the pipe a little at a time. keep track of how it performs at each length. once performance starts to drop, you've gone too far. at that point, just pull the pipe back out to the previous length.

[Watercadet]

I put an XTM .18 with a NTC3 header to match the rear exhaust on the motor with success. I never ran it with the direct drive, instead I did my own drive with a flex. I took an angle grinder to the triangle that the straight shaft was 'glassed to and ground it flat with the hull. The hole left by the old stuffing tube was perfect for the new tube I made. Most of the hardware I used is Hugley and I made the strut mount and rudder mount. I have not had a single stress crack yet and it sees some pretty high speeds. I think that I can attribute the little "wiggle" room where the flex hex ataches the cable to a stress free hull. The turn fin mounts missed the ply doubler inside, so I reatached them and used silicone between the fin and the sponson. There are pictures on here of the setup. http://www.radiocontrolzone.com/forums/showthread.php?t=157020
I have completly redone the rudder and mount and switched to a x440 and it really moves out. I am also looking at the Y537. Maybe that little motor can spinn some more :D

[BoatDoc]

me likes! i've been thinking about a cable drive for mine but wasn't sure about the surgery involved. now that she's down for other repairs...i may just do it!

[Watercadet]

Ya piece of cake! You can get the flex hex from Fine Design Marine like I did (make sure to order the 5mm threaded) and it screws on like a flywheel nut. The strut and strut mount are a little different .I made mine, but if you talk to your distributer they should be able to help you out.