Help Please!

[cleatus12r]

Originally Posted by redone1

Hello Bill and Corey,

The primairly use for this truck is to pull trailers.

Good platform to start with!

I plan on these settings on my near future PHP Chip:
Whisper - High Idle - Stock - Fuel Sipper - 60 Hp Tow - 140

Ok, so my question is this. Can I have RDS rebuild the injectors to stage 2's and control them to a stage 1 level with your PHP chip? Yes. Detuning the injectors is pretty easy to do. But there will be a few changes to increase the efficiency of the larger-nozzled injectors in a low injection rate situation.

I'm thinking it would be more cost effective to jump to stage 2's and control it with the chip versus realizing stage 1's are too small down the road and have to rebuild again. If I go to stage 2's now with a "detuned" PHP chip, then once all of my supporting mods are in to utilize stage 2's we can just reburn the chip to run them. Is this correct? Jim Rose thought it's no problem, but wasn't positve since he hasn't heard of anyone doing this first hand.

I should also mention that i may never decide to utilize the full potential of stage 2 injectors. Since I'm having my nozzles replaced, the starting cost is the same for stage 1 or 2 rebuilt from RDS. I may be happy with the power of stage 1's and never want more power.

The main concerns/questions I have in doing this are (assuming you can program the chip to do what I'm asking):
1. Fuel ecomony. Will my economy suffer any from running stage 2's with stage 1 programming VERSUS stage 1 injectors with stage 1 programming? Tuned properly, there won't be too much difference.

2. Will stage 2 injectors be subject to a lower life expectancy if not used to thier full fuel-flowing potential by running stage 1 programming? The life expectancy won't be an issue. On the other hand, it's the other way around as far as programming for larger injectors goes. Stage 2s will empty faster due to the larger nozzle holes. Running "Stage 2s" with standard "Stage 1" programming usually results in too much fuel in the lower RPM/Load ranges.

3. Is there anything else I'm completely forgetting here?

I would greatly appreciate your thoughts as soon as you can provide them. I need to let Jim at RDS know what I want to do. He should have received the injectors today and planned to get right on the rebuild.

Again, sorry for the long post!

Thanks,

Pete

See replies in red.

Common "Stage 2" injectors are rated at 160CC and have larger nozzles than stock. Conversely, "Stage 1" injectors are usually 160CC with stock size nozzles. It depends on the builder.

In any case, putting a larger nozzle on an injector that is the "same size" as another but with smaller nozzles will result in more fuel to be injected in any given amount of time. Thus running stock tuning or tuning designed for stock nozzles will usually result in too much fuel at the bottom.....too much black smoke and possible EGT issues.

In the case of "Stage 2" injectors, injection pulsewidth can be cut back some and injection control pressure raised slightly to keep the atomization level up.
The problem MAY arise with the Stage 2s that you will need more high pressure oil volume (larger HPOP) to keep up with the demand of oil that they will have over the Stage 1s since they are capable of flowing more fuel (longer plunger stroke) in the injection window that the Powerstroke engine has.

For towing, I think either of the two injectors will work out well for you. However, upgrading tuning isn't too much of a headache should you decide to "go big" later.