1972 GMC 400 BB stalling at stop light
 

Truck runs fine at first few miles. Then the idle will drop too low at a stop light and it will die. I have adjusted timing and set the idle speed higher so that when it goes in gear it will still run. Idle is set to 900 or so in Park and then in Drive it's at 650. When the engine warms up is when the problem starts. It will periodically "sputter" or gasp when going down the street, especially when I just touch the accelerator.

I recently put new HEI dist, new plug wires, checked for vac leaks, checked vac pressure and timing. Can't figure this out. Any ideas?

Re: 1972 GMC 400 BB stalling at stop light
 

Did you run a new hot wire to the distributor, or are you running off the line with a ballast resistor? That will cut your juice down several volts and ignition will be weak.

Re: 1972 GMC 400 BB stalling at stop light
 

Put some timing in it!
Then turn down that idle. At 900 you're kicking in the mechanical in the dizzy.

Re: 1972 GMC 400 BB stalling at stop light
 

What's your timing set at?