Rail pressure

[Whitetail Addict]

What are the advantages/disadvantages to raising rail pressure while tuning. I know some tunes/boxes raise rail psi and some don't, I was just curious as to why.
I know more consistent psi at wot, but is there anything else i.e. better fuel atomization, noticable power difference?
Any disadvantages, i.e injector (LB7 especially) or cp3 wear?

I tried a search, but nothing came up.

 

[racinmike77]

more pressure will allow more fuel to be injected with the same pulse width. Give brayden or mark broviak a call, aparently they have been sustaining 29000 psi in their trucks.

 

[SteveFord]

Better atomization will occur. You will get more fuel at the same pulse width if the pressure is increased. With that being said you could lower your pulse width while commanding more pressure to get the same amount of fuel I belive.

 

[super diesel]

Steve has it right. Don't bring pressure in to fast or you'll have a fuel pressure knock (I did anyway). This is how the original pressure boxes worked (PPE Duramaxamizer, VanAaken, DB Dynomite box). This is where the Duramaxamizer Tony (GMC_2002_Dmax) has for sale in the "Garage Sale" area is welcome (hand control for when you want the pressure). Think it's for an LB7 though. I brought it back up. What a steal.

 

[Whitetail Addict]

Thanks for the input guys, that helps me better understand it.

Is their anything in the fuel system, or anything for that matter, that can be harmed with too much rail pressure?

 

[Redbone]

Possibly erosion at some point?

 

[othrgrl]

As far as injectors with a stock CP3 you aren't gonna get the pressure you need to hurt them. There is a very noticable power difference if you are getting more rail pressure - but just because you demand it doesn't mean your CP3 will be able to supply it.

 

[malibu795]

Better atomization will occur. You will get more fuel at the same pulse width if the pressure is increased. With that being said you could lower your pulse width while commanding more pressure to get the same amount of fuel I belive.

Steve has it right. Don't bring pressure in to fast or you'll have a fuel pressure knock (I did anyway). This is how the original pressure boxes worked (PPE Duramaxamizer, VanAaken, DB Dynomite box). This is where the Duramaxamizer Tony (GMC_2002_Dmax) has for sale in the "Garage Sale" area is welcome (hand control for when you want the pressure). Think it's for an LB7 though. I brought it back up. What a steal.

i made a thread about this back in early 07 on diesel place..

in stock setting 23,000 doesnt come until 85% or better TPS is commanded,

curising is ~13-17000 psi pending load... stock

what i did what ramped rail pressure 23k form 1400rpm and 20% throttle on out. i noticed increased responsiveness to throttle in put as well 1-2mpg increase pending drining habite. egts went down 50-100* as well..

also had to re-addjust the pulse width tables as well... mainly they were setup for 1/2 the rail pressuire they were geting and timing tables... need to be adjusted... mainly pulling timing in areas... due to the fuel gettign in there faster

 

[super diesel]

You were right on with it too Adam. I remember the days of stacking the duramaxamizer with the Edge 90hp (highest that was avalable) and propane for the hot set up :bow:. :rofl: :rofl: :rofl:

 

[Whitetail Addict]

Thanks for the helps guys, I better understand it now.

 

[malibu795]

Thanks for the helps guys, I better understand it now.

you better..... i worked hard making htat readable :rofl:

 

[Whitetail Addict]

I appreciate it Adam, I got it loud and clear


I might have to try that, I like the idea of added throttle response and mpg's.

 

[LarryJewell]

you better..... i worked hard making htat readable :rofl:

yes you did, the spelling was spot-on, except for 2 or 3 words

 

[malibu795]

yes you did, the spelling was spot-on, except for 2 or 3 words

seams i am above avg last couple days :rofl:

 

[sweetdiesel]

more pressure will allow more fuel to be injected with the same pulse width. Give brayden or mark broviak a call, aparently they have been sustaining 29000 psi in their trucks.

remeber that the PW commanded is different than the PW at the end of the shot


Commanding a cp3 to full amount (WFO) will do this for short periods
its not a secret