A fuel rail kit for the 13B turbo rotary as fitted to Series 4 and 5 cars. The rotary makes this a particular case, since it runs primary and secondary injectors and the fuelling demands under boost are substantial, so rail volume and feed capacity matter more than on many piston engines. An aftermarket rail assembly gives you the internal volume and AN porting to run a properly sized fuel system with larger injectors, rather than working around a factory rail designed for standard output. Supplied as a kit. Check injector height and O-ring specification against your chosen injectors, as rotary rail spacing leaves little room for improvisation.