Japanese supplier denso, the world’s second-largest automotive supplier after bosch, has unveiled a new common-rail injection system with an injection prere of 2000 bar at the iaa. According to denso, the new system reduces nitrogen oxide emissions, engine vibrations and noise generation. It also improves the effectiveness of exhaust gas aftertreatment systems. The background: with common rail, fuel can be injected into the combustion chamber at will because the high-prere line, the "common rail," is kept under constant prere. The higher the possible prere, the easier it is for engine developers to achieve properties such as fine atomization.
Bosch also announced common rail systems with 2000 bar for 2007 in the spring, after the previous peak prere of its systems was 1800 bar. At 2000 bar, the injection technology with the "common line" now reaches a prere level that was previously reserved for volkswagen’s pump-dispense system. The high prere was considered one of the advantages of the pump-duct system, but this is offset by high costs and poorly controllable injection behavior – the pump is cam-controlled, which makes it difficult to variably control the injection timing in particular. Volkswagen also ultimately decided to switch to common rail, the first diesel engines with this system are installed in the vw tiguan.