Digital Injector Calibration and Balancing
Digital pressure sensing is used to read and and record injector data. The Pressure sensor is certified under ASME B40.7-2005 standards which permits accuracy to +/- 0.5%. Also due to the high speed cycling of the nozzles the new digital calibration equipment was selected due to its ability to read ALL pressure cycles that occur within a 10 millisecond window! To insure the highest level of accuracy the pressure resolution will be reduced to .068bar meaning extremely accurate pressure readings during all injector opening phases that no analog pressure gauge can display.
Due to the advances in modern injectors starting with the “Two-Spring” nozzle holder (also known as Two-Stage injectors) testing, repair, overhaul, and calibration is not permitted using Analog pump style testers for the reasons stated:
- Measurement accuracy
- Dead Space
- Pressure gauge quality class Link to Bosch “ESI” Document: Analog Tester not to be used
In House Digital Flow Validation (New for 2011)
Digital flow validation is used to read and and set every new nozzle that we sell. This is performed on the nozzles prior to installation allowing us to insure that every nozzle perform exactly to specification.
We can generate a complete report for every nozzle and compare every critical aspect of that nozzle performance. This is the equivalent of a “Dyno” for nozzles. We can evaluate delivery rate, peak delivery volume as well as response to flow at all ends of the flow range.
This new system uses state of the art Flow sensing technology which evaluates all flow characteristics by replicating the flow of the fuel passing thru the nozzle. Long gone are the fill tubes you may have seen, this new generation test bench samples flow rates as often as 400 times per second allowing a complete evaluation of a nozzles performance not previously possible.
This is especially helpful for companies developing a nozzle design or for the performance oriented driver/tuner looking to get the maximum performance from a nozzle combination.
Direct Injection (DI)
Two Stage Injector Calibration
Unlike older “IDI” or “Pintle” style injectors, two-stage injectors precisely meter and inject fuel at different intervals of every combustion stroke in order to control the pressure rise in the cylinder. The resulting softer rise in pressure greatly reduces the “Diesel Knock” formerly associated with diesel engines. This however results in an injector that cannot be set thru conventional methodology. Two stage injectors require multiple steps to insure both injection events occur within a very narrow window of pressure to insure that the fuel metering is not effected to maximize the ECU’s control of the engines combustion and power output. Each injection event in normal operation can be as rapid as 1.5 milliseconds in duration while tightly controlling the amount of fuel injected to minimize engine emissions output.
Set Pressure Ranges
Each pressure is set at a predetermined value based on the ECU fuel mappings expectation of injector performance. The pressures of each stage although independent have a reliance on each other to achieve the specified pressure that respective stage should begin to open at. Manipulation of one pressure without adjustment to the other will cause an erronious pressure change on the other. Anytime one stage is changed the other too must be adjusted and set accordingly.
Injectors have a certain expectation of durability in a specific application. The primary factor that determines the life of an injector nozzle is the quality of the fuel filtration. peak pressures at the nozzle holes can exceed 2000 bar, any amount of suspended matter can cause the fuel to act like a cutting jet rapidly eroding the nozzles precision machined hole geometry. It is accepted that no matter how good the filtration is, it is impossible to completely eliminate all particles from the fuel. So, even with ideal conditions some erosion of the nozzle is expected and will occur thus the reason nozzle fuel spray should be evaluated at regular intervals to reduce the likelihood of damage to the pistons combustion bowl and cylinders.
Click on the links below to take you to our Nozzle Selection Options: