Dead fuel Pump? Please help

[Slippery Nut]

I'm concerned one of my fuel pumps may be dead, as suggested by someone else. I've attached a portion of a datalog showing injector pressure drop of 27 psi in the 5,000 to 5,350 RPM range during WOT. The FPDC is less than 80%. I'm confused. Shouldn't the injector pressure drop remain pretty constant around 39 psi.

I've got a ported Eaton, 2.93" upper, SCT BA-2600 MAF, 47# injectors, 13 psi of boost and a KB BAP running with a Hobbs switch. The car has been dyno'd just under 500 RWHP.

This isn't consistent, but I have seen low pressures like this during datalogs of other pulls. When I had the car dynotuned for the SCT MAF, the A/F was in the middle upper 11's and it briefly jumped up just over 12 then went back down below 12 before the pull was over. This too concerns me.

If I'm barking up the wring tree, please educate me.

 

[decipha]

if its dropping that much pressure either the pump(s) are failing/weak, theres a restriction, poor voltage to the pumps, or the pump voltage table is really far out and it hasnt adapted yet

 

[Slippery Nut]

if its dropping that much pressure either the pump(s) are failing/weak, theres a restriction, poor voltage to the pumps, or the pump voltage table is really far out and it hasnt adapted yet

How does one go about troubleshooting the pumps as the problem?

 

[decipha]

the most common method is to wait for it to fail completely

if you verify the filter is good and thr line isnt kinked, and you have stable voltage to the bap and pumps then youve verified a weak pump

log the pump dc when it acts normal and see where its at, then compare that to when it runs lean

otherwise you can pull thr pumps and visually look them over, its common to see one pump melted and burnt up

If they appear good you can have them flow tested