1. What is EDM?
EDM or electrical discharge machining is a process using electrical current to drill or machine holes in steel and other electrically conductive metals. Using electrodes smaller than a human hair we machine precise, round, and accurate holes in the injector nozzle tip.
2. Why use the EDM process?
EDM processing does not harm or erode the internal sealing surfaces of the injector nozzle. A key part of nozzle operation is chatter and sealing. Positive sealing after the injection event has ended is important to lower emissive by-products. Positive sealing also helps in lowering exhaust gas temperatures by keeping the needle closed after the injection event has occured. Late needle opening from bounce or poor sealiing is eliminated with EDM injectors.
3. Why are smoke levels lower with EDM modified injectors?
Diesel sprays contain a population of superfine, vapor-like droplets. EDM injectors retain these characteristics. Diesel fuel is a newtonian fluid and as such resists preparation and air/fuel mixing. Additional spray holes of smaller diameter will atomize fuel into smaller droplets. This leads to enhanced low engine speed air/fuel mixing, increased power levels and reduced particulate and smoke emissions.
4. Can you explain the history of the project?
F1 Diesel began development of EDM modified injectors using CAD and CFD software to get a basic foundation on what sizes, spraying angles, and number of holes to use before we ever machined the first nozzle. Extensive computer simulation and modeling directed the begining research and the first few sets of nozzles were contract machined. Chassis dyno and road testing soon followed. The first dyno results showed an additional 70HP and 150 lb. ft. of TQ. Daily driving in the summer months showed better smoke control and low end power response.
The 24 valve injector was then added to the research and the project continued with more help from CFD software and a few local University computers ( -: Several sets were built and the 24 valve dyno and road testing began. Over 200 dyno runs using different trucks and conditions started in the spring/summer of 2002. Over 150 different designs and configurations were considered.
5. Are all EDM processed injectors the same? Are they safe?
When F1 Diesel first began EDM research we had several designs we felt would be a good starting point. After completion of the CAD drawings and computer simulation we began looking for contract shops that could perform the work. Out of the first 7 sets we paid to have done only one set was within tolerance enough to even test. Needless to say the contracting abiltiy for quality controlled EDM work was not an easy thing to find. Wildly different results from expensive EDM shops all over the country from East to West left us wondering what to do next. Finally, we settled on a quality shop and began the relationship of having them machine the nozzles to our tolerances. This eventually lead to the decision to purchase our own EDM machine with the capabiltiy to hold tolerances for this precise operation. This gives us great flexibility to make design changes, test new ideas, and never wonder if the tolerances are tight enough or not. It also lowers the cost of the injectors for the consumer.
Safety! EDM machining itself is not a dangerous process if the proper guidelines are followed. Many stock injector nozzles are actually manufactured using this process. F1 Diesel has resolved all of the safety issues with its nozzles and stands behind them 100%. We begin with a blank nozzle constructed of a special alloy steel that is heat treated and precision ground to our specifications. This gives our nozzles the durability to outlast even stock Bosch nozzles. None of the nozzles used in the EDM program are stock Bosch parts.
6. How do you rate your injector power levels?
F1 Diesel used a chassis dyno (DynoJet 248C) to measure all HP gains at the rear wheels. These gains were made at sea level using uncorrected numbers. All HP gains were made with a single turbocharger.
7. Do you build custom injectors for twin turbos, etc.
Yes,we do build custom injectors for special circumstances like twin turbos, in-line "P" pump conversions, etc. Since we do all processes in-house we can offer this service. We are currently testing and tuning a 24 valve engine using a twin turbo system that recently made over 700HP at the rear wheels using a stock VP-44 injection pump. This translates to a 1/4 mile elapsed time of 12. 03 @ 114. 5 MPH in a 4 wheel drive truck that weighs 7000 pounds.
Attention: TDR Forum Junkies 
But now, that you mentioned it, marine version does have a different pump and cam... 
) DD2's are pretty smoky if I don't watch what I'm doing. 
But can manage EGT/power levels easily with the multi-stage fueling box. I'd stay with 2's for a lot of heavy towing/low boost operation-where a turbo/driveline upgrade is out of the question. 
