Pecos..
you actually run 4.8 (4 cells)....try 5 cells (6volts)..it'll give you a bit torque...and speed
Sail Servos 4.8V Power 6.0V Power 4.8V Speed 6.0V Speed
S3801 156 194 0.33s 0.26s
S3802 122 153 0.70s 0.56s
http://servocity.com/html/s3801_hi-torque_sail.html
http://servocity.com/html/s3802_arm_type_sail.html