Our pressure-operated soft snake robot promises inherent flexibility and versatility to operate on complex and unpre-dictable environments compared to traditional snake robots made of rigid linkage chains. We previously presented a theoretical framework to describe its unique dynamic behavior and experi-mentally verified the accuracy of this model. This previous work had some drawbacks; the maximum center of mass velocity of the previous soft snake was one tenth its body length per sec-ond and the dynamic model could not predict the behavior of the robot when following non-linear trajectories because of a lack of frictional torques. In this paper we introduce the next gener-ation of our soft robotic snake we call the “WPI SRS”, which can locomote ten times faster than the previous version. Addi-tionally, we present refinements to the dynamical model that can predict both linear and rotational motions of the robot. Finally, we demonstrate the accuracy of this refined model through ex-perimentation. 1