Hello all,
There are many topics and threads regarding which injector nozzles are best, I searched the web and reference material and found that many of the DN0SD nozzles are similar, what I did find was the pintle hole diameter is 1mm for many of the nozzles. What was interesting was the differences in needle stroke, See catalog:
www.hidrojet.ro/pdf/nozzles2.pdf. I examined an old nozzle from my 5000TD which has DN0SD293 and I found that I could insert a 1mm wire through it (snug), I then setup a dial indicator and measured the stroke of the needle from closed position to when it bottoms on the shim (fully open) and it was 0.75mm. It matched the information shown in the aforementioned catalog. Of interest was the Mercedes nozzle DN0SD220 it is indicated to have a 0.95mm stroke. My theory is if you want more fuel you need several things,
1. Increased needle stroke.(different nozzles or modify the shim) 2. Increased (internal) pump pressure (external lift pump?). 3. Compensate increased timing advance (from pump internal pressure) with injector break pressure adjustment. I suspect that keeping the hole size at 1mm will help with atomization. The break pressure debate on needle lift by combustion pressure may not be that critical, as the surface area of the pintle is smaller than the surface area of the needle that the fuel contacts in order to lift the needle so you have to factor that. I believe break pressure more critical for timing and atomization. So I know there will those of you who will pick this apart, I am not claiming this to be the final word, like the title says Injector Nozzle Theories. What I would ask is if you have some used nozzles that you can measure to elaborate on this theory that would be welcome as well as you thoughts on the preceding points.
Topic: Injector Nozzle Theories (Read 1938 times)
