Bob, I'm using two seven cell Duratrax 2500 NiMH battery packs connected in series for each motor. They are connected in series with that "Y" connector you can see in the image. The runs are 10 to 12 minutes long. I'm usually motoring along at 3/4 throttle. That was the setting I was using when Tom was shooting that video of my PT boats. Dan.
http://www3.towerhobbies.com/cgi-bin...&I=LXXUN9&P=SM