Sounds like your choke is not working properly. It sounds like you have a manual "heat actived" choke. The metal tubing is a choke tube that brings heat to your choke from the exhaust manifold. The heat gradually deactivates the spring in the choke as the car warms up. It has to be attached to the exhaust manifold correctly, but may have worked loose.
I had this setup on my 67 Mustang and got rid of it. You can buy an electric choke that bolts right on and not have to worry about the metal choke tube. Take it off. Or if it is unkinked and long enough, wrap around the exhaust manifold and that will sort of work.
Look at the butterfly of the carb when the engine is cold. It should be almost closed and then open just a crack when you start it. It should stay closed for a while and gradually open when the car is warmed up. You need a shop manual for your car, it explains this and other little things in detail. It also covers every function of the car. Worth the $35 investment. Look on eBay for the shop manual. Parts store should have an electric choke for less than 20 bucks.

<font size=-1>[ This Message was edited by: 67VertMustang on 10/27/06 1:40am ]</font>