What max psi can the pump be set at, I know it's adjustable but would like to know how much. Thanks for any and all info on this pump!

 

I have the same pump on my 3rd gen and it is set at 42 psi at idle

 

I wasn't aware the GSL392 is adjustable. It will pump to capacity at whatever restriction it sees. So in the 3rd gen, it is seeing 42psi of restriction/backpressure in his system in your setup it may see more or less, or to whatever the regulator added/supplied with the kit or installed is set to. I bought a Swagelock poppet valve I am setting to approx. 16 psi for my bypass line from the VP44 supply banjo back to the fuel tank. The pump will deliver whatever amount of fuel is possible at that backpressure throughout the rpm range. Clear as mud?

 

according to GDPs website the pump is rated at 130 psi, so i guess you could actually set for 130 psi at idle wouldn't that be nuts!!!http://www.glacierdieselpower.com/pr...?pf_id=3929852here's the link to that pump too.

 

I personally ran the GSL392 at 140 psi last weekend on my truck, and it didn't stall.
But I did not put the 140 psi on a VP44 if this is what your plan is. I suspect the VP44 would stall if I did. Expensive experiment.
The pump itself is not adjustable unless you will vary the voltage or modulate the duty cycle. But the pressure can be adjusted using pressure regulators, etc.
-P