I have a Holley 14 psi lift pump from NAPA on my 01 cummins and it feeds enough fuel for my 125hp injectors and EDGE comp box but im thinking about stacking the EDGE with a TST box.
Would that lift pump plus the stock pump be able to run those things?

 

What do you mean by plus the stock pump? Are you thinking running them in parallel or series? I ran a stock intank pump in series with a Car Quest block mounted pump for a little while. The idle PSI was way too high for my liking though, 31PSI. In parallel, you MIGHT be ok if one of the pumps is regulated.

 

I ran mine in a series, the stock pump is on the tank and the Holley pump is on the same line just a little farther up. The way i set it up it will run the injectors and comp box and hasnt starved it for fuel.

 

What kind of fuel pressure do you have now? At idle and WOT?

 

99 psi but my gauge is wired wrong so idk

 

wow

 

get a raptor 150 set it at 19 psi at a idle and call it good

 

Mines set right around 21-23 idle... but i run some pretty harsh conditions... it will sink down to around 116 lowest wide open throttle full boost loaded towing... on older filters.. it wont move with new filters..

 

If you don't know your pressure, are you sure your not starving it? Just because it doesn't buck and kick doesn't mean its getting the minimum 10PSI to keep the electronics cool. I'd suggest getting the gauge fixed, then try other things.