LB7: Rail PSI ?'s
- Thread starter JJK-
- Start date
Because pressure is a measurement of restriction it doesn't exactly work like that. Even if you set it at 28 psi as the injection pump draws more fuel i.e. creates less restriction the pressure will drop. Technically the lift pump flows the most fuel at 0 psi.
I'll get a gauge installed.. Can the psi be regulated via a regulator screw or does the spring need to be switched out?
It's a titanium 95... I'll do some checking and see what I come up with...
Thanks..
Only on the lb7 and LLY do you have to keep it around 8 to 10. The LBZ and LMM benefit from and can handle the added pump pressure. Mine would go all the way up to 30 before it started to lope. I have set everyone I have ever installed on a lbz or lmm at or above 25 psi...
I somehow missed this is an lb7 though, my bad. Lack of sleep from my 2 week old must be getting to me...
I somehow missed this is an lb7 though, my bad. Lack of sleep from my 2 week old must be getting to me...
Did you put a new spring in the fass? if you didn't touch the fass the 95 is only going to pump 7-10 psi not 28 psi
Nope, I haven't touched it. I need to get a gauge or see if I can hook it up to my insight and see where I'm at...
I took the truck out for a few WOT tests and noticed I'm getting 19-20psi of boost. Not sure that this would have anything to do with the rail pressure, but I'm sure it is effecting all the coal I'm dumping and why it's not cleaning up. I'm thinking about pinching off the hose on the waste gate to see if it helps out the boost and cleans it up, of course this would only be for test purposes...
I pinched off the waste gate, well at least part way, my vice grips are very small, and it hit 24psi according to my insight. I recently read that the insight reads boost from the map sensor and the map sensors are scaled at 22-25 psi, can anyone confirm this? If so I'll have to hook up a manual gauge to get an accurate reading.
Yes the ECM only reads up to like 24 or 26 psi iirc. Drop $28 on a boost increase valve and lose the vise grips lol
Yep, for sure. I'll order one tmrw. The vice grips were temporary
Now if I can get my rail pressure figured out I'll be set.. Thanks..
Sounds like it has too much pulse in the tune. It is probably smoking because it is losing rail psi from too much pulse. Log it or ask your tuner how much pulse it is. Maybe they didn't adjust for the bigger injectors.
Only on the lb7 and LLY do you have to keep it around 8 to 10. The LBZ and LMM benefit from and can handle the added pump pressure. Mine would go all the way up to 30 before it started to lope. I have set everyone I have ever installed on a lbz or lmm at or above 25 psi...
I somehow missed this is an lb7 though, my bad. Lack of sleep from my 2 week old must be getting to me...
That is completely unnecessary. I run 12#'s from AD 165 with the stock pick up and made almost 1000 without losing rail pressure on 2 stock pumps.
You mean more pressure before the CP3 won't magically fix the rail pressure :roflmao:
Good suggestion.. I'm going to his shop tmrw to log it and check a few other things.. Thanks!