All I could ever find is this...
Servos: One SF-1 standard servo for throttle, SF-2 high torque servo
for steering (70 oz/in .20 sec @ 4.8V or 90 oz/in .16 sec @6V)
I plan on putting the sf-2 on the throttle and getting the SF-5 from the XL for my steering it has like 360 oz. of torque or something like that.