Industrial injection is the way to go. If I wasn't so far in the boondocks I'd get my injectors built and balanced by a local shop and have them put 100% over nozzles in. If Ur like me right now drop ins are your best bet. If your going with 300s I'd dial the fuel pump wayyy back. Especially if you're fighting heat now. Diesel is opposite of gas. More fuel = more heat less fuel in most cases is less heat. This makes me suspect injector(s) are a culprit if your fighting heat. But a hx30 is pretty small for any performance. Not saying it's doable but the turbo effeciency map is something like 33psi anything over just makes heat and kills performance and thee volume is mid range. If you have the 4500 apart do the 5th gear mod, the nut likes to come loose and it goes south fast from there. Also look into killer dowel pin fix definately don't want that happening either!
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