The b16 would be an improvement, but if your going to go through all the wiring loom problems, it may as well be for a b18!
The engine went on it 26 hours after i bought it, need a new one but finances will only allow for a ZC, 1.6 dual carb, a direct replacement for whats already in it. I was just driving along and then a very loud knocking came from the engine, i pulled over and turned off the engine. Ive come to the conlcusion its the cam shaft... Maybe i should have kept the micra...