Engine Dies When Warm

[gulffishin]

I haven't posted in a while, but I am need of some professional help

I have a 64 with a 283, Edelbrock 600cfm performer carb and Edelbrock performer rpm intake and after I drive about 10 minutes it starts to run really weak-like it's starving for fuel. If I keep the throttle down it will keep running, but if I let off-like slowing down for a light, it will die. It will start back up easily, but if I don't stay on the throttle it will die almost instantly.

Funny thing is, if I start it in the driveway and hold the throttle open 1/2 way for 10 mins it will not act up. I have went about an hour before revving and idling and holding the throttle in the driveway and it never dies.

It started doing this about 5-6 months ago and since then I have rebuilt the carb, changed the plug wires, and put fresh gas in it, but it's still doing it.

It ran fine up until about 5-6 months ago.

I give up ::throwing towel::

What do you guys think it could be?

Thanks for your help