Will this combo work?

[Tylerfishsmith]

Hello, new to the electric scene and am trying to power a boat. Hull will be approx. 5lbs. I have a Graupner speed 700 brushed motor 9.6V, Jeti JES 600 Navy esc, Turnigy 5000mAh 2 cell 7.4V Li-Po battery and a Thunder Power 2200mAh 11.1V 3-cell Li-Po. Am told by some this may work with one of these batteries, but I have some doubt. Do not want to run the Ni-MH batteries to save weight. Any thoughts on a different combo. Maybe a new brushless/esc combo? Any input is helpful. Want to try and use as much as I already have obviously. The speed 700 flex shaft and outdrive are already installed, so I am sure I could adapt a different motor to this if need be. Space is a problem so I need to keep it compact.

[rc2266]

Type of boat?

[Tylerfishsmith]

Scratch built design. Nothing similar that I have ever seen.

[rc2266]

Any pics of design, and what are you looking for, race, sport?

[Tylerfishsmith]

Don't have any pics as I am still building. Need to figure out the drive sytem. can I use any of those Li-po packs with my brushed motor? What esc to use?

[rc2266]

Just check specs on esc, try not to max voltage on it.

[Make-a-Wake]

That motor runs well on 14-16 cells nimh or 4s lipo.............thats it sweet spot. How long is the boat........Vee hull? 5 lbs is kinda heavy for just the hull...............

[Tylerfishsmith]

Boat is 33" long-stepped v-hull w/ narrow beam. 5lbs. is everything, using the speed 700 and 3 servo's w/ lipo battery and all gear. Of course this is approx. that I am trying to stay under for a scratch built. The speed 700 is a little heavy. Sounds like I need a 4 cel battery or change motors. Wondering if there is any weight savings going to a equivalent brushless motor? Any idea's? Thanks for the feedback.

[Make-a-Wake]

The 700 will run it, but not real fast, you may get bored with it quickly and you'll need a smallish prop. I'd throw a 4074 in it. Leopards are about 90 bucks or you could go with this clone for $54.........run it on 4s.

http://toyabipro.com/product_337.html

You could also run a lower kv 4074 on 6s: http://www.hobbyking.com/hobbyking/s..._Inrunner.html

This ESC will work if you dont overprop it...........keep it in the x440 range

Great for only $49: http://www.hobbyking.com/hobbyking/s..._Boat_ESC.html

[Tylerfishsmith]

Wow!!! Great info...Thanks. I don't have a water pick-up on the 700 outdrive for the esc. Not sure if I have any room to mount one. Is this a must for short runs? Not racing, just experimenting. Any idea's on a 4s battery? Have hundreds to choose from. Thanks again for the input.

[srislash]

crap 002.jpg
This should be the drive you speak of? This is in my old school box and the water cooling was real cheap to make up.
BTW anyone want it?

[Tylerfishsmith]

Mine is different. The rudder is behind the prop. My transom is just wide enough to fit the outdrive. It is actually a RC plane sponson converted to a boat. I have extebded the drive to put prop lower in the water so hull can lift completely out of the water, there in lies my dilema.