Heat Soak
 

Just wondering if your supply is -10 and return is -8
why does the one to the pump (supply) look smaller in the picture?

ob

Bad photo I guess?? Thanks for the tip.

Heat soak
 

Let us know what you find out or what works

thanks,

Bob

How much horsepower is the engine making?

That's a lot of pump for most applications.

And if the engine is stalling with little to no throttle, it's not a venting problem.

Only about 525 at the crank. I’m thinking I still have a kink somewhere. Gonna do some experimenting this weekend.

Ok, well I've ruled out a kink. Car is still doing the same thing. Warmed up after about 10 minutes, fuel pressure starts dropping, then the car dies. I've been having voltage issues and it seems when the fan kicks on, that's when the fuel pressure really drops. I've spoken to a few members and they recommended "0" gauge wire to the battery and frame. I'm currently using 1 gauge. Seems like this would make sense right?

I've never heard of "1" gauge wiring -- typically wire is referred to as "aught" -- so ONE AUGHT -- 1/0 --- or TWO AUGHT -- 2/0.....

1/0 being smaller than 2/0....

1/0 can carry 300 amps for 19 feet --- 2/0 can carry that a bit further.

Are you running 1/0 ?? Or 1 gauge ???

The key is grounds must be as good as the hot side of a circuit. You could conceivably have a "high resistance" connection somewhere in the system - on either the ground or the hot side - and as this connection heats up - it's resistance increases.... until it can't carry the load.

I would "ASSume" there are RELAYS used for switching loads such as this pump and your electric fans etc?????? You could have a bad relay and as it heats up it breaks down.... I've had that issue before.

It's just plain old 1 gauge. However, I've seen a chart for gauges/amps for how many feet etc. They recommend 3/0AWG for my setup. Battery is in trunk and everyone seems to think the wire I'm using ain't cutting it. Makes sense since as soon as the fan kicks on, my fuel pressure drops. Plus I ate an Optima yellow top and a 140amp alternator awhile back. Think the smaller wire would do all that?
Oh and I've got relays all over the place. Car only has 350 miles on it.

Heat soak
 

Running 2 0 on the firebird for many years
It is actually welding cable. I have it on ground side also
I also ran a separate ground back to the battery from my relay panel
Relays help but with electric fans, msd, fuel pump and I have an electric water pump all those things add up to a lot of draw on the battery and alternator

You can also not have too many grounds. Our panteras need multiple grounds
added due to the poor original grounding. I have seen some high powered cooling fans requiring 50 amp fuses. That is a lot of draw. Add your load up to make sure your alternator can keep up with your draw

Not an expert but been there before

Bob

Is your fuel pump near the trunk where the power comes off the battery?

Also, those crimp connectors on the pump look questionable, especially the black ground wire. I could see the bare copper wire thru the back of the yellow plastic insulator.

I had a bad crimp connection on the fuel pump relay. The car would run fine around town, but on long drives (2+ hours drive straight), the car would loose fuel pressure, and stopped running. Baffled me awhile, until the connection failed completely (crimp location burned/melted insulator). After that, I pull and discard those plastic insulators, crimp/solder the connections, and put adhesive backed heat shrink over the soldered joint.