Pressure Box questions (Predator)

[Toshiro]

... I've recently installed a rail pressure gague that I received from 'DieselPower' via the group buy... Thanks Wade... .



I have a predator box on my '05... I was suprized to see just how quickly I can max out the rail pressure gague (26500psi) and suck the fuel pressure gague down near zero with the box set on 100hp... . Once I roll on the gas, it doesn't matter if I let up or not, the rail pressure stays maxed until I stop accelerating and begin to coast a bit...



I have since removed the box... . I need to find out just how bad this is for my truck before I put it back on... . I have a dozens of question but here is a short list... .



How much pressure is too much?



I only turn the box on to mess around... never tow or cruise with it, is occacional romps ok or is high pressure damaging every time?



When the box is installed but turned off I get higher boost and rail pressure levels than if I unplug/remove the box, so it must still be doing something, right? Is the box not really ever 'off' ?



I understand that there is a relief valve that may open if pressure is too high. Where is it and can I tell if it has ever opened?



I appreciate any advice/input...

Thanks in advance



Toshiro

 

[Diesel Power]

the higher boost and higher rail pressure is because of the boost fooling the box provides, your seeing max rail pressure instantly is great, that means everything is as it should be, or at least as the box advertises. running every day is no problem, other parts on your truck will feel it before your fuel system does, it was designed by bosch to opperate in around 30kpsi envirement, the only weak point is the relife valve, it is rated at 26,500psi.

 

[Toshiro]

Diesel Power, thanks for the reply... .



first of all, please forgive me, I'm kind of ignorant about this stuff... I hope I'm not asking stupid questions

... I assume that the relief valve will release pressure as a certian point... I think that I have read on the TDR that the relief valve can fail and it is an expensive part to replace... any truth to that? Or is it ok to hit max pressure and just let the relief valve do its job and stop worring about it... lol... .

... Also. . the box is easily getting my stock turbo to about 35+ psi... what are the limits of the stock turbo?...



Thank again

Toshiro

 

[Diesel Power]

Diesel Power, thanks for the reply... .



first of all, please forgive me, I'm kind of ignorant about this stuff... I hope I'm not asking stupid questions

... I assume that the relief valve will release pressure as a certian point... I think that I have read on the TDR that the relief valve can fail and it is an expensive part to replace... any truth to that? Or is it ok to hit max pressure and just let the relief valve do its job and stop worring about it... lol... .

... Also. . the box is easily getting my stock turbo to about 35+ psi... what are the limits of the stock turbo?...



Thank again

Toshiro

the stock turbo is about 40 psi max, and the relief is a yes and no question, some fail and some work well, you dont need to run wide open all the time ---do you? :-laf

 

[GWBourne]

the stock turbo is about 40 psi max, and the relief is a yes and no question, some fail and some work well, you dont need to run wide open all the time ---do you? :-laf

YES!!! lol. . one problem i have noticed about my VanAaken box... 45lbs of boost on a stock turbo... OUCH



anybody have a grand or three i can have. . lol

 

[Toshiro]

If the relief valve has been opening should I be able to see any signs of it?. . fuel or something?...

 

[Diesel Power]

If the relief valve has been opening should I be able to see any signs of it?. . fuel or something?...

one way to see if it works is to after shut off go to the tank and listen for fluid return, like a few short bursts.

 

[RDyson]

The relief valve will eventually fail. It is not meant to be routinely "opened".



The relief valve will just dump the fuel back to the tank. It won't leak outside to the ground. If it is damaged or stuck open, you will see a loss of power high EGT's and of course low rail pressure.



If you had not gotten the rail PSI gauge, you would have kept using your box and never known the difference. People have put millions of miles on their trucks using the same boxes and never had a problem. But now that you know just how high the PSI is, makes you nervous--huh?



One other thing to consider is injector failure. Running HIGH pressure has caused problems in the past. You can do a search and find plenty to read.

 

[Toshiro]

RDyson, you hit it right on the head... I am nervous now that I know the true pressure... lol

. . I thought I would be relatively safe with the Predator box because I heard here on the TDR that a few dealers installing them... but I guess all mods hurt a little... I will do a search on the injector issue... . Just another thing to add to my list of items to worry about that I probably don't need to worry about... lol. .

... one last question about the valve... will it keep the rail from every exceeding 26500psi?. . I am assuming that it will always open at a certain point... Is that the case?



... thanks again guys...

Toshiro

 

[Diesel Power]

RDyson, you hit it right on the head... I am nervous now that I know the true pressure... lol

. . I thought I would be relatively safe with the Predator box because I heard here on the TDR that a few dealers installing them... but I guess all mods hurt a little... I will do a search on the injector issue... . Just another thing to add to my list of items to worry about that I probably don't need to worry about... lol. .

... one last question about the valve... will it keep the rail from every exceeding 26500psi?. . I am assuming that it will always open at a certain point... Is that the case?



... thanks again guys...

Toshiro

typically yes, but i have seen them hang up and not open... ... .....

 

[Toshiro]

if the valve fails to open will the pressure gague exceed 26500 and let me know it is happening. . or does something else limit the signal the gague is getting therefore the max on the gague will always be approx. 26500?...

 

[RDyson]

There is a max reading that the sensor will get to. But I dont know what that is. My first box was an EZ and after I read about the injector issues, i bought a TST. It does timing and duration, no pressure.



I think it was a posting of injectors replaced by DonM that showed the pressure cutting in the injector.



I still run my EZ--but on level 1 to compliment the TST instead of level 4 by itself.