[ChrisG]

Humm - what you did was shut of the second choke barrel.

What you have is a Single Progressive Weber.
These carbs were fitted to Fords etc.

It works on the principle of having two barrels - One is a largish one which controls low end speed tickover etc etc.
The Second is the Progressive barrel. When you put your foot down, the second barrel will open allowing more fuel and air to pass into the system.
These things were designed to give fuel economy while having that extra "umph!" when you needed it.
This carb is certainly not the best in the world as it is designed for a specific engine.

Actually I have probably an identical carb sat in my garage which I never used. It cost me £15 ($25) from a scrap yard.
It seems that the PO had enough of the FI messing around (I know that feeling) and decided to go for a cheap option.

Knowing this now, you need to check a few things.

Firstly as MJHanna said, check if you have a Bosche 009 fitted. You can tell that by seeing if a vacume chamber is attached. If it is you need to change the dizzy for a 009 - they are relatively inexpensive ($60?) and through using a machanical advance they will solve many problems.

Next up however is the carb itself.
If a 009 has not been installed I can understand better why the car is possibly running rich. In order to get a quicker advance on the car, the jets have been set up to pour fuel in. If this is the case, then a 009 and rejetting of the carb will fix it.
If a 009 has been installed the problem is still most likely down to jettting again.

Venturie size will also affect the fuel mixture.

Needless to say though - if you are going to replace the original FI unit at some point, I would start looking for one now as to be honest, resetting up the engine with the carb will most likely be more hassle that fitting the FI back (and then again, maybe not !)

Anyhow, that me done

Chris G