• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

High Injector Pop Pressure

6.5L said:
mind=blown. Lot of info to take in
Click to expand...

Yep, it's been quite some time since I studied up on this stuff as I am now high pressure common rail injection. It isn't a simple add pressure and increase atomization type deal though. Also keep in mind as pop pressure goes up, your timing will go down as it will take more travel of the pumps plugers to build up to the higher pop pressure. I know some guys tryed this on DP years back on the DS-4 pump(and also the DS-4 hybrid pump), and somewhere north of 3,000 PSI pop pressure resulted in a locked up and sheared off rotor head. The DB2 pumps can take more pressure than the DS-4 pumps can, but I don't rememebr how much more.
 
It doesnt seem a bump up to about 2300psi would cause anymore issues. I believe it would still be benificial to atomization and wouldnt hurt anything. Wouldnt you just have to adjust the timing to match the injector delay?
 
I went lower to get more fuel and for timing. Timing sounds the same though. This was the Mercedes nozzle. A stock nozzle will have higher psi after its open, simply from restriction,which helps the chatter. Longer travel nozzles ,like marines, probably won't have an increase of pressure from restriction.
 
I had to advance the timing when I swapped out long body 6.2 injectors for higher pop pressure 6.5 short body nozzles. I had left the pump alone to try and keep the set timing from the rebuild it had before I got it. The pop pressure affects timing.
 
I read that the injector pop pressure settles after a while. Wouldn't a set pop pressure of 2300 settle to like 2200 after a while, and be right where the marine nozzles pop at?
 
I wouldn't think 2400-2500 pop pressure would hurt anything, but much more than that would cause other effects I would think. Personally I would run the pop pressure range that the nozzle is designed for though to avoid the "other" issues that have been posted.
 
Subsribed. Anymore info on this? Currently running 2800 psi injectors and trying to figure out why my van won't start on Jet fuel and diesel combo, when it ran fine on WATF blends.
 
Your head and rotor are worn. Thin fuel will just leak through at cranking speed. I had to lower my pop psi from 3800 psi down to 2000 psi so it would start hot. To run high pop psi injectors you must have a very good head and rotor. Or run waste oil with a worn pump.
 
Its supposed to be new. Oh well, I'll just put my brand new head and rotor on and inspect an injector to see how they are working with waste oils.
 
You must log in or register to reply here.
Back
Top