" From: "Jim Blair" <carnuck@xxxxxxxxxxx> " " A: Why are the injectors screwed into the intake and not the head then? on a diesel?!? since the fuel is ignited by the compression of the air in the cylinder, how do they avoid premature ignition if it's injected through the intake valve during the intake stroke? and it would make the phrase 'injection timing' meaningless. i'm assuming the valve isn't cracked open near tdc for the injection, also incidentally venting compression pressure into the intake. i don't see any way this could work. you have to inject the fuel near tdc on the compression stroke, when the valves are closed. the only indirect injection i've ever heard of uses a prechamber in the cylinder head that the injector and glow plug [if any] project into. it's possible that the geometry of the head and packaging factors could have the injector mounted on the intake, but it'd still have to inject into the cylinder or a prechamber, not the port. " From: adh@xxxxxxxxxxxxxxxxx (Sandwich Maker) " " " From: "Jim Blair" <carnuck@xxxxxxxxxxx> " " " " It's called indirect injection and quite few older engines worked that way, " " including the IH 7.3L used in Fords and the Nissan 3.3 in Jeep trucks. " " indirect injection does not work through the intake port. it is true " that many truck and all sub-truck diesels are or were idi; i forgot to " add that in addition to scaling down, they're also generally more " rpm-flexible than direct injection, though computer control is erasing " that. ________________________________________________________________________ Andrew Hay the genius nature internet rambler is to see what all have seen adh@xxxxxxxxxxxxxxxxx and think what none thought _______________________________________________ Amc-list mailing list Amc-list@xxxxxxxxxxxx http://www.amc-list.com/mailman/listinfo/amc-list