If you can get a coupler thats 5mm to 1/8 or what ever your prop shaft maybe a very good motor would be the tacon 3674 6t 2800kv from hobbypatz in the car motor section. This is the motor http://www.hobbypartz.com/96m214-3674-2800kv-6t.html. If you have to stick with the coupler that you are using coupling the titan to the prop shaft this would be a good alternative motor http://www.hobbypartz.com/96m285-2858-3200kv-9t.html these should get you decent speeds with the 3s pack. You need to get a speed control, something that can handle 60amps should work with these motors but to be on the safe side get something with 120amps which will give good head room. A prop thats 40 to 42mm be ok.