twin nitro

[superjet183]

i was thinking about building a twin engine nitro boat. has anyone done this and does anyone make a kit? i was thinking a vee hull with twin 15's or 21's. what would be a good hull to start out to modify? thanks

[Ron Olson]

Twins aren't an uncommon boat. There have been boats built with 4 engines. The running gear is available, but if you are asking this question you may not be ready for twins yet. They are a real pain to set up and to synchronize and the handling is another matter all together with 2 or more props turning in the same direction makes for more severe prop walking. There is nothing like seeing a twin run when they're dialed in but too much hassle for all but the most experienced racer. If you decide to try it, go for it!

[laxmasta2039]

twins are great to run, always a show at the lake, but think about how exact and precise ya gotta have the engines/drive systems........one small piece of dirt creating friction of one tuned pipe being angled slightly differently will make you boat track to one side. it's also very expensive to buy two of everything.


joe

[rcboats2]

Twins used to be my specialties, however, I spent more time arguing about why I built them than actually running them.
I prefered them in Cats more than vee's because Vee's cause even more prop walk than a cat and provide you a lot more room to work inside the hull than a Vee would.
I've had twin .21, 45, 67 and 80s. I've used OS, OPS, K & B and Picco's. I actaully had the best luck w/the OPS .80 for some reason. They all tend to run when you first run them and sound like a Harmony Orchestra, just sounds beatuiful, until you throw it in the water and one motor stalls. The one motor causes so much drag on the boat it's amazing how hard you have to oversteer to retrieve the boat.
If you got the guts go buy a DPI 1/4 scale and run twin 7.5 OBs. Those are a kick.
My advice, save your money on the 2nd motor and build one single engine boat that is extremely fast. That way no one will tell you "I told you so!"

[laxmasta2039]

well,
there ya go- real life experience!!

[Hammerhead]

Hello! I had a twin .21 mono. . It ran super fast in a straight line , but it got a little crazy in the corners. The guy who made me my .21 spent some money on his own .46 VX-M twin. Getting the crankshaft reworked so that one of the engines would run backward to counter the torque of the props. It worked. And his boat cornered fine. No one here has been successful in getting .21 RX-Ms to run smoothly backwards. They drum rotor engines are the most difficult to do this with. Anybody had any success doing this?
Hammer

[Dirt Dummy]

Hers my eagle with twin CMB .90"s. I love it! http://www.midmad.com/dirtdummy/boat.JPG

[Hammerhead]

Hey DD!
One great thing about Riggers, you don't have to counter spin the engines.
Looks really cool.
Hammer