No way to answer such a general question. Procedures calling procedures however doesn't cause bad performance. Badly written code and poor indexing causes poor performance. You either need to do a general tuning exercise on your database, starting with identifying what *is* causing the problems, or you need to get a 3rd party in to do one for you.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability