ROTREX C38 addstar ROTREX C38 Compatible with engines below 3000-6000cc; Power Range C38-61 ：272-557 hp Power Range C38-71 ：280-620 hp Power Range C38-81 ：300-660 hp Power Range C38-91 ：354-720hp Peak impeller speed：90000 rpm Gear ratio：1:7.5