any one know anything about the audi 90?

hey the names mark and i am currently deployed to iraq. i am trying to put my money to good use,so i bought my first german car. its a 1994 audi 90 CS quattro. i am new to the euro scene so i need some help. i need to know if there is any otehr engine that will have compatible parts (aftermarket), and where do i start. im already making plans to widebody the car but all the body work is going to be custom done by me. so i guess my issue here is performance ,how do i unlock the german horespower.