[Gaz64]

I would say that your intake combo gets a little warmer than normal (acceptable) especially after engine shutdown, heat soak.

By the sound of it, you have both issues.

It has been compounded by the change to winter blend which has more low end vaporising composition. The fuel vaporises at a lower temperature.

The engine starts ok hot because most has evaporated. When cold it is more than likely flooded with liquid fuel, hence the flooded starting.

I would take the carb off, drain the bowls, take the bowls off carefully to inspect the back of the power valve AND the area within the main body where the manifold vacuum is presented to the back of the power valve from the base of the throttle body. Hope that makes sense.

There is a recommended torque figure for the power valves.

I fitted a QFT 750 to a mates car after I stripped it for inspection. Has never played up.