i was only curious if there was a benefit to ordering the c code nozzles versus the j code ones. i have been lead to believe that the c code stuff was for the civillian set ups not the heavy duty military stuff. i have apparently drug this discussion on to long for some folks so i will seek elsewhere for the rest of the answers.
The C-code nozzles had a spray pattern that made the most efficient use of small precombusion chambers. It was only slightly different for J-code, military, and commercial-duty nozzles.
Over the years, new nozzles have taken the place of older ones - so one general--purpose nozzle fits all.
A new nozzle like the Bosch numbers that Rock Auto sells will work fine in all the 6.2s.
Over the years. 6.2s and 6.5s used many different sized precombustion chambers - and OEM injectors were calibrated to match them as perfectly as possible for best fuel mileage, power, and/or both. These differences are minute.
There were at least five different sized pre-combustion chambers used over the years in 6.2s and 6.5s. If somebody was still actually making nozzles to match each one, they'd cost a fortune. Buy the latest nozzle and you'll never know the difference (from what it might of had orginally).
Chambers ran from "no mark", to one-dot, two-dot, three-dot, two dots with a T, etc. Heads also variied and light-duty heads often had big valves and heavy duty heads has small valves.
The smaller chambers with the OEM nozzles could make pretty good fuel mileage but did not have the power potential when a turbo was added and/or a turbo added.