66 Cuda vacuum line diagram

Kerry123 said
That's what I tried, the car started and idled but when I put it in gear it went womp womp womp and would not drive.

The valve has zero function in that situation, same as bypassed.
Here is a little read on it.
CAP/CAS Distributor Vacuum Advance Control Valve

Have you reset the timing and idle mixture without it?

Alan