They were part of the British Rail Class 47 order , but differed from their classmates by being fitted with a Sulzer V12 12LVA24 power unit producing , as opposed to the standard 12LDA28C twin-bank twelve-cylinder unit of the remaining fleet .
They were part of the British Rail Class 47 order , but differed from their classmates by being fitted with a Sulzer V12 12LVA24 power unit producing 2650 bhp , as opposed to the standard 12LDA28C twin-bank twelve-cylinder unit of the remaining fleet .