Westfield (Mass.) Contributory Retirement System is searching for an active domestic large-cap growth equity manager and a core-plus fixed-income manager to run a combined $45 million, said Lynn Rea, retirement administrator. State Street Research currently manages the assets in an active balanced fund, with roughly equal portions of equities and fixed income. Ms. Rea said officials of the $115 million system decided to conduct the search because of BlackRock's pending acquisition of State Street Research. She noted that officials will reconsider the firm in the search process. The retirement board will consider proposals for separate managers or one manager for both asset classes. Ms. Rea said the board plans to have a manager or managers in place by early May.