The engines produced a total of  which gave the ships a maximum speed of . Wivern reached a maximum speed just over  during her sea trials on 4 October 1865. The ships carried  of coal, enough to steam  at .
The engines produced enough power to achieve a maximum speed of the ships. During her sea trials in October 1865, Wivern reached a maximum speed just above . The vessels were supplied with  of coal, enabling them to travel for at .