Volume splitter for a fuel delivery system

A radially deformable volume splitter of an emulsion injection common rail for a fuel injection system of a spark ignition engine, wherein the volume splitter is tubular and elongate, extending along a longitudinal axis from a first end to a second end;

• and wherein the volume splitter comprises:
• a deformable longitudinal slot operable to radially deform the volume splitter from a first state for insertion into a cavity of the emulsion injection common rail to a second state for use inside the cavity;
• and
• a set of grooves, arranged on an outer surface of the volume splitter, for connecting an inlet of said cavity to one or more outlets of said cavity, in use, the set of grooves comprising:
• an inlet groove for connecting to the inlet of the cavity, the inlet groove extending axially from a first end to a second end;
• and
• first and second end grooves for connecting the inlet groove to an interior volume of the volume splitter around the first end and the second end of the volume splitter;
• wherein the first end groove extends from the first end of the volume splitter to the inlet groove, the second end groove extends from the second end of the volume splitter to the inlet groove, the first end groove connecting to the first end of the inlet groove and the second end groove connecting to the second end of the inlet groove thereby fluidly connecting the inlet groove to the interior volume of the volume splitter;
• wherein a cross-sectional area of the first end groove is greater than a cross-sectional area of the connected inlet groove, and a cross-section area of the second end groove is greater than a cross-sectional area of the connected inlet groove.