Can you code a 1300 key to a 1600 felicia ecu?

I don't see why not, the immobiliser boxes are the same.

Thanks for the info

Yes you can, the key is coded to the immo box only, then the immo box is coded to an ecu, in fact it is possible to match the immo unit to virtually any ecu of that generation even ones from vw's, I have in the past matched the felicia immo box to a mk3 golf vr6 ecu just to test a concept when I was considering an engine swap in that direction.

TeflonTom.