6.4 Powerstroke tuning for large injectors

[h00vy]

I've dropped in some Industrial Injection 20% injectors in my 6.4 when I rebuilt it. That and a Colt stage 2 cam. The truck hazes heavily at idle and at certain RPM (around 2,000-2,500) while climbing a grade (meaning decent throttle input), it surges pretty bad.

I have several custom tunes that I bought for the stock injectors several years ago and I like 1 or two of them pretty good. Does anyone have suggestions on what may need to be changed in the tune to clear up the haze and other general improvements?

I have tried adjusting the Pulsewidth to lean out the fuel below 6k psi fuel rail psi (it idles around 5k psi & .50ish PW) and smoothed it, just to see if that would change anything. It didn't. I would think it would require some timing changes and other tweaks.

Oh, and Industrial Injection have not been very forthcoming with specs (flow rates etc) for these injectors, so I don't have much data to go on besides the 15%-20% that they call them. They've also stated 50-60hp.

Any thoughts?

[HattDaddy6.4]

Hey man, have very similar issues but with 100% over injectors. I have stage 2 cam, forged pistons and big 476 single. Looking for any assistance in modifying tune to account for large nozzles and limit idle haze. I'm gonna keep tweaking things with the tune and let you know if anything helps!

[JaegerWrenching]

Have you updated your PW map to match the new injector? You need to know where those injectors start flowing more vs a stock injector and also make sure your surge isn't fuel pressure related. As the injector starts to open up more it'll drain the rail and the PID control will start to over/under compensate creating the surging affect. You'll need more amperage on the regulator where these injector start moving more fuel at the same duration. Sometimes the surge is too much fuel and it's putting out the flame intermittently.