350 not getting enough fuel

[OrangeC20]

So it won't let me reply to my other thread on this topic. But here's an update. My electric fuel pump is mounted right after the gas tank on the frame rail. It runs awesome in the mornings when its 30-40 degrees. When I get off work at 5 or 6 when its warm it runs horrible and acts like its not getting enough fuel. 1974 Chevy c20 with a carberated 350, hei distributer, stock quadrajet carb, fuel pump is rated for 5-9 psi and is not adjustable. Any help is appreciated and sorry if I don't reply its because the forum won't let me

 

[Jrgunn5150]

Is maybe the choke not calibrated correctly?

 

[1987 GMC Jimmy]

So it won't let me reply to my other thread on this topic. But here's an update. My electric fuel pump is mounted right after the gas tank on the frame rail. It runs awesome in the mornings when its 30-40 degrees. When I get off work at 5 or 6 when its warm it runs horrible and acts like its not getting enough fuel. 1974 Chevy c20 with a carberated 350, hei distributer, stock quadrajet carb, fuel pump is rated for 5-9 psi and is not adjustable. Any help is appreciated and sorry if I don't reply its because the forum won't let me

It very well could be the choke. My first thought after reading this was vapor lock because you said it runs well cold and not so much hot. I don't know. If it cold starts well, and hot starts bad from the get go, I'd follow up with the choke.

 

[OrangeC20]

Forgot to mention that it typically only does it at higher rpms. Don't have a tach but would guess around 3500-4000 and I'll wire my choke open tomorrow and see if that helps

 

[Jrgunn5150]

Is your float set right?

So it runs properly, all morning at all RPM?

Then runs like poop later in the afternoon, everytime?

 

[Quadrajet Power]

Check your choke first to make sure it is full open when engine is warm as mentioned above.
The Quadrajet has a small fuel bowl, and doesn't require much pressure to deliver for any engines needs.
If your choke is open, then your float may be saturated or not set correctly, which will not allow enough fuel in the bowl. Today's fuel really can mess up older internal parts, and most store bought kits aren't any better. A good build with good parts might be a good idea for your quadrajet.

 

[OrangeC20]

Thank you everyone for your input but none of you were correct. One of my buddies was working on my truck and it was low voltage to the fuel pump. Guess I otta check the odvious stuff out first next time