05 Cummins Tune Review & Write Error

Hey all, I've been SLOWLY building a tune for my truck.
The truck: 2005 3500 DRW NV5600 9500lbs unloaded. The Mods: S&B Air box, 4" exhaust to 5" stacks, Bosch 25% over injectors, 6.7 cross over tubes, Fass 150.
Regularly hauling .5-1 Ton in the bed and towing 4000-10,000 Lbs.

Since the injectors and initial tune upload the truck has been quite hazy. The base tune HpTuners spit out to start with had a very retarded SOI table. Sections of the SOI was near -8*. I have remapped the throttle scale, removed limiters, increased boost, new timing table, adjusted PW for 25% over injectors, raised and smoothed fuel pressure, and changed idle rpm for colder temps.

The last 2 tunes removing post injection, adding more timing in the low throttle and cruise range and smoothing my rail pressure and SOI table have made a much linier power band. Removing the post injection has also snuffed the top end which is peculiar.

My next goals are to remove some of the haze from idle and cruise range. Tune in the Airflow table instead of WG duty cycle to get the boost I'm looking for. And continue to add more cruise and low end timing to gain some economy back. If anyone can enlighten me on why getting rid of my post injection has robbed top end power that would be great. From my research it should not have effected overall power. It did also clean up a lot of the smoke in my daily driving.:usa:

Attachment 153699

Pull the fuel pump relay and be sure your batteries have a solid charge on them before writing the tune file. If you want the wastegate to behave like a mechanical wastegate you’ll have to go to a mechanical wastegate. Stock form it’s electronically controlled using the charge reference tables to regulate desired airflow.

Quote:

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Originally Posted by Jim P 2.0

Pull the fuel pump relay and be sure your batteries have a solid charge on them before writing the tune file. If you want the wastegate to behave like a mechanical wastegate you’ll have to go to a mechanical wastegate. Stock form it’s electronically controlled using the charge reference tables to regulate desired airflow.

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Thanks Jim, I was able to get the tune to write properly by not being lazy and dragging out the charger.

Using the charge reference tables should make it possible to set the lbs/min to hold the boost your looking for. Say 35PSI. An old second gen I had, I used a fuel pressure regulator for a boost regulator on the factory waste gate actuator. I set my fuel pressure regulator to 40psi, once you hit your set pressure the access pressure was sent to the waste gate and walla. I was a fan of the theory that it held the waste gate shut longer then the traditional charge reference line always feeding pressure to the waste gate actuator. It makes it easier for drive pressure to push past the gate with boost on the actuator at all times. Was it that important on my 62.5mm hx35, no probably not. But did I over engineer it to do EXACTLY what I wanted, Yes.

And that's what I'm going for with tuning the WG based off Airflow not just a 50% duty cycle. Which is netting 35PSI currently.