[IMPORTANT] - My application performance

My application is using Firebird 1.5.2

I have at my database:
- 150 Doamins
- 318 tables
- 141 Views
- 365 Procedures
- 407 Triggers
- 75 generators
- 161 Exceptions
- 183 UDFs
- 1077 Indexes

My question is:

Postgre SQL will be more faster than Firebird? How much (in percent)?

I need about 20% to 50% more performance at my application.
Can I get this migratin to postgresql ?