Lift Pump Pressure Question

[dpuckett]

Hi all; I am here at Mom's, (translation- ULTRA slow dialup- search takes more time than I have at the moment), and I was wondering what the lift pump pressure should be? I hooked a line up to Mom's boost gauge (that is as of yet uninstalled ), and got a steady 7psi at idle, and light throttle. At WOT, 30+ psi boost, it sucked down to 5psi. Is this normal? I realize bgilbert has a 2nd Gen LP, but his readings were still higher at the get together last month. Anyone else? What are you seeing with your stock LPs?



Daniel

 

[bgilbert]

Daniel that is very good pressure. 5-7psi is spec idle and wot. Mine dead LP was 3psi idle 0 wot. PM me with a #, I'd like to call you.

 

[cerberusiam]

What Bill said. Thats good numbers for a diaphram pump.

 

[BushWakr - RIP]

I agree, although 5psi might seem low it is higher than the "book" spec of 3psi... .

5psi is good at WOT... . depending on how much fuel your pulling of course you can certainly get away with that pressure... . until you get a bit wild... er... enthusiastic... ummm... . wacked out like the rest of us...



pb... .

 

[dpuckett]

Bob, I aint sent the pump out for a buckeye upgrade yet , so I aint getting too crazy- saw 40psi and 1350 this afternoon. Next paycheck will get it gone through and freshened up, along with checking injectors. Cruise (65mph) EGT is about 800; normal is 650. Boost is the same as normal, filters are good.



Re-tested it today, and dropped 1/2 psi acorss the board from last weekend. Mom's has the same numbers as mine- 6. 5 & 4. 5. This is post filter. Thanks for the input, guys. I have learned there is the spec, and then there is real life, and they often differ, for better or worse.



-DP

 

[bgilbert]

Cruise (65mph) EGT is about 800; normal is 650.

650* normal for intercooled maybe but not nonIC'd right? I would always see about 800* at cruise when I was charge air cooled challenged. Sounds like you got two good lift pumps between the two trucks. When you get the bucks and want more, then a piston LP should be in the works.

 

[JLEONARD]

I'm at 650/700 F at 65/70 on a level road

Jay