Q: Reman 600 cfm 4 bl eddlebrock carb on 390 preformer low rise intake on stock reman engine starts when throttle won't stay running

It sounds like your timing may be off slightly. Be sure the timing is at least very close to what it should be and then you can adjust the carburetor from there. I would also check to be sure the vacuum advance (if this carb has it) is working correctly and that the vacuum lines are run properly. Other possibilities may include a lack of sufficient fuel supply resulting in the motor starving for fuel when you apply the throttle. This can happen when there is a blockage or lack of fuel flowing through the fuel lines or if there is not enough fuel in the float bowls when needed. If you need further help with this, please reach out to us here at YourMechanic as we are always here to help.