Smarty: Wild Rail Pressure?

I thought AD150 wasn't adjustable?

If it is..... how do I do this?
 
have to pull the return out and play with the spring. might want to call AD and see what they suggest for springs. whats fuel pressure currently at?
 
D45 said:
Brett Williams at II said to lower lift pump pressure to 13 psi and this will increase rp

?????
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Rail pressure is a separate system completely than supply pressure, the only way to are going to effect rp with supply is if you don't have enough fuel to feed the CP3. I have been told over the years that more supply pressure is better, but I have never noticed a difference running 10psi all the way up past 30psi. I have also witnessed a truck make within 1% of its dyno number with the airdog switched off. Not recommended just forgot to put the fuse in after switching tunes.)
 
D45 said:
Brett Williams at II said to lower lift pump pressure to 13 psi and this will increase rp

?????
Click to expand...

I don't see how that would have an effect on anything. My AD is set at 15psi and will drop to about 12psi if I lay into it and my RP never really changes. The 03-04 trucks just run lower RP than the newer ones. I never see anything over about 12k psi while cruising.

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Feed PSI does effect RP at Idle and some during cruising and WOT, under most conditions adding RP needs to be manage RP just increasing RP does not mean added HP, any GP will pull down most lift systems, make sure you talk to some one that can relate what's necessary to manage lift and RP correctly.
 
Mark Nixon said:
So, you're running the 6.7 injectors on the '03-early '04 ECM with no cold start issues?

Interesting.

Mark.
Click to expand...

Sorry I didn't respond earlier.

They are injectors meant for an 03-04 they just have a different designed injector body. I believe it is more like the design for the 6.7. I don't know exactly what is different but I do know that I can not change the injector nozzles with another stock set of 03-04 nozzles.
 
TCDiesel said:
Feed PSI does effect RP at Idle and some during cruising and WOT, under most conditions adding RP needs to be manage RP just increasing RP does not mean added HP, any GP will pull down most lift systems, make sure you talk to some one that can relate what's necessary to manage lift and RP correctly.
Click to expand...

Just clarify, and this is where I get into trouble in most cases. If the cascade valve is set at (lets say) 75 psi, that means that 75 psi is the pressure that is suppling the 3 pistons in the CP3. What I mean by this is that is you have enough supply pressure from the lift pump that you always have a positive pressure to the gear pump on the back of the CP3 and it is not more than 75 psi at idle. How would that have any affect on rail pressure?

I am asking a serious question, not trying to be a smart a$$ (like I am most of the time).
 
I removed the T&C Diesel CPRV 26K valve and threw a rail cap/plug in there to see what happens

For 5 min of work it should rule something out

the top of the cprv was pretty wet and had diesel fuel inside the little depression area on top of valve

Should it be dry?

I swapped it out for the rail cap......

I was also getting a 2-3 crank start and now its a 1 crank start

Time for a test drive
 
That's why we raised all LVs to 30K, 32K 34K. Looks like you need the upgrade, let Me know I will take care of it. There will always be fuel on the top of the valve, the return circuit on the CP3 will make its way to the top when running.

On Edit That-That's
 
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How would or how will the upgrade help with rail pressure?

The rail cap didn't help at all......still can't get above 15k
 
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