63 Dart overheating issue

Mineallmine said
I have a new rad cap for the car as well, but not installed yet. I doubt that will change anything as the temperature goes up to almost hot before the pressure pushes past the cap.

Lets start with this. The inability to hold pressure anywhere in the system will allow the temperature to rise once vapor begins to form in the system.
See if you can get your hands on a tester. They usually have adapters to check caps as well as the system.
Looks like this

Side note: A radiator without a recovery tank will be full cold about an inch below the cap.

Mineallmine said
Let me correct that. I am actually at 7.5 btdc. I forgot I adjusted it. I tried 2.5 and 5 but it didn't like it. Starts and runs much better at 7.5. maybe I'll back it off again to see if it changes anything

Mineallmine said
I think my mechanical is fine. I know when I rev it when I was setting it with vacuum disconnected it changed with rpms. I'll check the vacuum. The hose is connected to the correct port on the side of the carb.

Mineallmine said
Stock pulleys.
Adjusted timing to 2.5 BTDC and adjusted carb to run well with timing setting - no change.
Temp hits about 250-260 and is boiling over.

With Regards to timing:
A. Its seems close enough that should not be the cause of overheating.
B. RPM RPM RPM
The RPM of the measurement is important. Centrifical advance adds to the intial above 600 or 650 rpm.
So 2.5* BTDC at fast idle is retarded.
2.5*BTDC should be at slow idle specification. I'll guess around 600 rpm is the spec. Could even be 550 rpm "with lights on" (so the alternator is adding load).

Mineallmine said
Oh, and one thing I forgot to mention. I checked the vacuum at the carb. Basically none at idle but gets stronger as rpms increase. Don't have a vacuum guage so i can't tell you exact measurements. Also again I checked mechanical advance with the vacuum disconnected and as you increase the RPMs the timing changes as well so I'm confident that is all correct as well.

No vacuum advance at idle is correct.