Having fueling issues. Would like to start a discussion on possible solutions.
My problem is (I think) either fuel pump gets too hot on long drives or a lose electrical connector.
Symptoms: after a long drive in 90*F heat , the car will loose fuel and fall on its face. If I down shift and give it some more throttle it will come alive again.
Another symptom is if I had been driving for a while and turn the off, then try to restart in less than a minute or two, the fuel pump won't prime. After about 15 minutes (during this time I was wiggling all the fuel pump related wires) it will prime again and start fine.

Supercharged (kw) 430whp.
2008 w/ returnless fuel system
Walbro 255 fp
SOS direct wire relay fuel pump kit
SOS (in fuel pump hanger) fuel pressure regulator.

I have replaced the Walbro once already and I don't believe the first one was bad now.

I have a new tyco 75 amp relay on order (not yet installed) to replace the one that came with the SOS battery direct relay fp kit.

I am sending (not yet installed) the electrical connector that goes on top of the fuel tank , to SOS to have them install the modified electrical pins. My first attempt at doing this myself wasn't 100% with the super small pins and double barrel crimper. It seams that when the car is acting up, if I wiggle this connector then the fuel pump will prime. I tried taking this connector off and cleaning the contacts and applied di-electric grease.

I also ordered (not yet installed) a new oem fuel filter sock. Currently using the one that came with the Walbro.

I also ordered (not yet installed) a new oem fuel pump relay (the one that goes under the dash)

 

I'm no where near your power but in cali I notice when its really hot 100 degrees and long drive my walbro is extremely loud and acts similar to yours.

 

I wonder if installing a fuel cooler would help? Or maybe some heat shielding under the gas tank

 

It's the walbro 255 pump. I had the same problem here in FL. At first I thought it was due to having low gas in the car, so I kept the car at half tank, problem was still there. So I upgraded to the Aeromotive 340 and everything was good. No rewiring needed.

 

Getting it,
Are you 06+ ? Return-less fuel system?

 

I changed out the oem pgm-fi fuel pump relay with a new one. Drove her for about 2 hours today with no problems! I think I fixed it!

 

I have the basically the same setup and make the same power.. I also had this same exact issue.. after about an hour it would get much louder, and just like you said, start falling on its face.
I tried many things and finally I swapped out the walbro to a fullblown.
Never had an issue again and its completely silent.

 

It died again today. Gonna try new map sensor, then if that does not work I'll bring it to my local tunner and test it on the dyno. Running out of ideas.

 

I also suspect the little white tube in the fuel pump carrier that goes from the fuel pump up to the fuel line. Maybe it isn't sealing properly. I mean, I use really good fuel line clamps on the fuel hose on the fuel pump, but then that little white tube just has a ribbed rubber end on it.

 

That good hp number. What size pulley and injector you are running?