The engine is slow to return to idle. All of a sudden this is happening. I checked the ported vacuum can of the distributor and its working. I also checked the springs under the rotor and they are intact and the weights move as they should. I found that the stops are small silver and the two springs are blue. I checked the basic setup on the 8479 distributor and its supposed to have silver heavy springs. Sooo I have changed that some time in the past and I cant remember doing that. I ordered a spring kit for this distributor and will things back to stock settings.
At the intake manifold I checked the vacuum hoses for the power brakes and the transmission modulator and they check good, no leaks. I need to check the vacuum hose connection for the vacuum modulator at the transmission and make sure that is not leaking.
If none of those are the problem, I will disconnect those hoses and cap and then check the idle. Plan is to eliminate all vacuume connections. If after all of that, then I need to take a look at the carb itself.
UPDATE:
I took a look at the new linkage I put together to replace the original. The replacement has a mild carbon steel 1/4 rod threaded on each end with heim joints(rod ends). This linkage is considerably heaver than the original but its also very sturdy. I ended up adding another throttle return spring. So now there are two springs, a smaller one nested inside a larger one. That additional spring is what I should have had all along. I also greased the pedal throttle linkage at the firewall location(looks likes it has never been done before). Tomorrow when I get the chance I will start the engine and check to see if these latest changes were effective.