Helping a friend out 63 chrysler 300 413 long cross ram all stock restored car. has what appears to be factory carbs so I want to keep it that way I am goin to replace accell pumps as they only squirt when you hit it hard. I will check float levels etc while inside main question is in between the idle adjustment screws there is a large adjustment screw I have never seen before Its about 1/2 wide has a spring on it and looks just like the idle adjustments usually there is a vacuum port there. does anyone have experience with this and is it factory carb for this engine?
