1989 turbo capri

[fasty73]

Has anyone increased the boost in one of these without upgrading engine parts? If so how much is safe? I am putting a boost controller on mine next week and was hoping to run 13PSI as 6PSI is standard and a little boring.
Yes, I have too many cars. I also have a worked AU sedan and a worked EF wagon as well as my NC Fairlane oh and don't forget the turbo Mazda V6 929 and the NX Coupe.