slant 6 running odd

rastaswinger,
Sounds to me like it's in the fuel system, by chance what year is the car and engine? They had a recall on the 1976 -77 cars as they had a fuel distribution problem and some folks had been killed while turning corners, the engine would die, I know I had one. They told me to return the car for a different one or they would just let me out of the balance, so I just returned it. I tried different carbs and fuel pumps but to no avail. The only thing that I can tell you is to replace the entire fuel system and the tank with a aftermarket one and then rewire the tank sending unit. I'm thinking that they have a vapor lock issue or a sending unit issue as this would only happen when turning left, so it had to be a problem in the tank, is what I'm thinking.
Let us know what you find, but this is where I would start looking.