Attention: TDR Forum Junkies 
Some very interesting HPCR Injector Facts
High Pressure Common Rail Injectors
The clearance between the injector needle and the guidance is 2µm.
2µm ? =. 0000787 or rounded UP 8/10,000ths of an inch. A VERY tight tolerance. By design, we need this needle to open & close (lift & lower) with the alignment as correctly as possible, to insure the male conical tip of the needle correctly aligns with the female conical seat, to insure proper opening & closing events.
At 2000 rpm this opening & closing event is completed 2000 times every minute, including the pilot and main injection events. At 3000 rpm, 3000 times every minute & @ 4000 rpm this opening & closing event occurs 4000 times EVERY MINUTE.
Now lets take a look at the pressures this needle tip is exposed to. Oem values are up to 23,500 psi. Some tuning enhancements run these pressures up even higher ? Wow. Now we have fuel exiting the nozzle holes at OVER 23000 psi under full power demands. The needle is moving up & down vertically & RAPIDLY ( up to 4000 times per minute) opening and closing, injecting a precise amount of fuel with each & every event.
Lets take a better look at these nozzle holes. It makes sense that they NEED to be in a uniform pattern, and with a uniform size as to provide equal pressure against the needle, within the guidance, to insure the needle is allowed to stay centered. If the nozzle hole pattern/placement is incorrect, or if even ONE SINGLE HOLE is not PERFECTLY sized and matched to the others, these mis matched internal pressures will force the needle off center causing premature wear to the guidance.
One single hole in the nozzle, not in the EXACT proper placement, or of the EXACT proper size, IDENTICALLY matching the others, will accelerate the demise of the guidance, needle and the preciseness of the event. While the injector will "work" with these eccentricities, it WILL have an adverse effect on the injection quantities and the overall life expectancy of the injector. If the conical tip of the needle is not allowed perfect alignment with the female conical seat, we can NOT have a crisp/clean event as the original design intended.
If all these pieces of the puzzle are not exactly correct, it will accelerate tribological wear, because the needle has to slide into the seat before it fits perfectly! Does it seem like the life span of current after market modified injectors is NOT as good as the originals ? One small change in design alters the whole make up or function of the system. For every action, there is a reaction. In our examinations of the "Various Manufacturers" offerings, we are not finding small changes. We are finding LARGE changes that radically effect injector performance and life. We understand WHY our those manufacturers performance injectors deteriorate rapidly. It's also easy to understand why high horsepower CR motors are frequently experiencing injector related engine failures.
High Pressure Common Rail Injectors
The clearance between the injector needle and the guidance is 2µm.
2µm ? =. 0000787 or rounded UP 8/10,000ths of an inch. A VERY tight tolerance. By design, we need this needle to open & close (lift & lower) with the alignment as correctly as possible, to insure the male conical tip of the needle correctly aligns with the female conical seat, to insure proper opening & closing events.
At 2000 rpm this opening & closing event is completed 2000 times every minute, including the pilot and main injection events. At 3000 rpm, 3000 times every minute & @ 4000 rpm this opening & closing event occurs 4000 times EVERY MINUTE.
Now lets take a look at the pressures this needle tip is exposed to. Oem values are up to 23,500 psi. Some tuning enhancements run these pressures up even higher ? Wow. Now we have fuel exiting the nozzle holes at OVER 23000 psi under full power demands. The needle is moving up & down vertically & RAPIDLY ( up to 4000 times per minute) opening and closing, injecting a precise amount of fuel with each & every event.
Lets take a better look at these nozzle holes. It makes sense that they NEED to be in a uniform pattern, and with a uniform size as to provide equal pressure against the needle, within the guidance, to insure the needle is allowed to stay centered. If the nozzle hole pattern/placement is incorrect, or if even ONE SINGLE HOLE is not PERFECTLY sized and matched to the others, these mis matched internal pressures will force the needle off center causing premature wear to the guidance.
One single hole in the nozzle, not in the EXACT proper placement, or of the EXACT proper size, IDENTICALLY matching the others, will accelerate the demise of the guidance, needle and the preciseness of the event. While the injector will "work" with these eccentricities, it WILL have an adverse effect on the injection quantities and the overall life expectancy of the injector. If the conical tip of the needle is not allowed perfect alignment with the female conical seat, we can NOT have a crisp/clean event as the original design intended.
If all these pieces of the puzzle are not exactly correct, it will accelerate tribological wear, because the needle has to slide into the seat before it fits perfectly! Does it seem like the life span of current after market modified injectors is NOT as good as the originals ? One small change in design alters the whole make up or function of the system. For every action, there is a reaction. In our examinations of the "Various Manufacturers" offerings, we are not finding small changes. We are finding LARGE changes that radically effect injector performance and life. We understand WHY our those manufacturers performance injectors deteriorate rapidly. It's also easy to understand why high horsepower CR motors are frequently experiencing injector related engine failures.
