A
BMW B38 series engine would seem the logical choice. The two 1500cc turbo variants are 100kW/138bhp and then a big jump to 170kW/228bhp although limited to 112 hybrid and 228i FWD application.
For this reason the B38A15M0 138bhp version would seem the only choice within the range given there is a RWD application and hence manual gearbox option. In keeping with the trend this would still allow modest increase in performance when mounted on CX platform over outgoing model and hopefully allow entry level pricing.