If you have a CAT 3406E that is in need of a set of injectors, or you are looking to upgrade the injectors on your CAT 3406E / C15, hopefully this is the information you are looking for!
Now I am just a stooooopid turbo guy, but its pretty hard to take advantage of a larger turbo without a good set of injectors adding fuel to the fire.
While I am no expert, I have been slowly trying to compile helpful information to share, as I cant seem to find a source that has this information readily available in a consumable format.
The first thing worth pointing out is that there really isn't a readily available aftermarket / new / upgraded injector set. Unlike the turbocharger market, it seems like there really aren't any aftermarket injectors for the Caterpillar platform at all, its just new CAT injectors, or remanufactured injectors that originally started life as cat injectors.
From what I understand, this is mostly because the injectors have to be so precise to function properly. Which is another reason that its important to make sure that you are purchasing injectors from a source that you can trust.
In the Caterpillar community, you will often hear people refer to injectors as 57s, 55s, or 59s. What these fellas are referring to are the last 2 digits of a particular part number. For example, "55s" are OEM part number 10R0955.
While there are many OEM injector sizes and countless cross reference numbers, I'd like to focus on what I believe to be the most popular.
Lets talk about these in size order:
57's or 10R0957 or 10R8501
These injectors commonly came stock in 550HP rated Cat 3406E/C15 engines like the 6NZ. Great for a stock 550HP engine, or one turned up slightly with a tune, manifold, or 78MM turbo
58's or 10R0958 or 10R8502
These injectors are a little larger then the 57s, but also came stock in some 550HP Cat 3406/C15 engine models. The higher flow rate can certainly support a larger turbo like an 80MM / 1.45 AR and upwards of 750HP.
55's or 10R0955
The 55s are the beginning of the "big dawg" injectors. These injectors commonly come from marine or industrial Caterpillar applications. Injectors of this size can support an S500/GT55 (88MM, 91MM) etc and should be capable of supporting 1000HP
59's or 10R0959
We'll end our list with the infamous 59s. This injector should be capable of north of 1000HP and it the largest stock injector that I am currently aware of.
Now, like any performance upgrade, you cannot just throw a set of injectors in your engine and think you're ready to break horsepower records. These injectors are to be used with support upgrades. IE - if you install a larger injector set, you also should be looking at a larger turbo, maybe a cam, and programing to match. Whenever you upgrade a component, you need to upgrade the things that SUPPORT IT as well.