Ford 1.1 Weber Carb advice(mainly 34ich)

Check all of the vacum lines going to the carb before doing anything else as the VV carbs use vacum a lot to have them run correctly, also have you checked to see if the engine has been converted to run on unleaded petrol i.e. does the head have the hardened valve seats fitted needed to run on unleaded as a lot of the early escorts (pre 91) did not which would explaine why you have the pinking.

A compression test would be a good thing to do as it would show low compresion if the head needs some valve work doing.

Rule out everything else before you start changing all the expensive bits.