Increasing the pressure on the rail helps in such a way that higher pressure, of diesel is injection atomizes the fuel better , and also the simple rule that higher pressure means more quantity of fuel [this is very small increase].
Diesels usually work well with higher pressure ,higher fuel pressure mean finer atomization [simple comparison between DI and IDI systems]and hence efficient burning. In common rail thou the pressure is constant through out the range, increasing the pressure by even few bars in the system will give big benefits. case with swift diesel with peggy back, only care has to be taken while doing this is the pressure should be kept in check, since the pumps in mechanical there is a chance of over pressure which can harm the pump,rail,injector and other plumbing.
In mechanical systems one can increase the pressure but the benefits are not that much in small engine. In larger engine like the cummins with mechanical pump one can increase the bhp torque and also peak rpm of the engine by changing couple of spring on the pump. |