Quote:
Originally Posted by Psycho  Based on what I have read CRDi engines tend to use a high pressure fuel pump and use a common rail to pump in fuel to the injectors at extremely high pressures. The injectors are fired multiple times to get the desired quantity of fuel into the cylinder this is what I am assuming is a limiting factor to the additional quantity of fuel going into the system.(I may be wrong here please educate me if I am.)
As far as the add on modules that you get tend to increase fuel pressure and also some units tend to increase the injection pulse duration to increase the power output of the engine. |
The part of a High pressure pump used to pressurize the rail is correct. The multiple injection are used to reduce the noise created by DI engine due to fuel exploding, they are called pre injection [used to ignite the fuel slowly ] so the noise is reduced,thats why the new peizo injectors are used on High end cars[they have low response time] and are good for upto 5 injection per cycle. The firmware is deigned so that they only required fuel is brunt including the preinjection.
The peggy back systems are designed mostly to fool the ECM in thinking the pressure in the rail has dropped and so it tends modify the signals to maintain the pressure in the rail, this inturn adds little more fuel in the cylinders.some are designed to modify the signal from the ecm to the injectors itself and vary the injection pulses.