What are the common modifications for increasing performance in an Audi TTRS?

I am looking to improve the performance of my Audi TTRS and I am wondering what modifications are typically done to achieve this. I am particularly interested in modifications that are specific to the TTRS model.

One of the most common modifications for increasing performance in an Audi TTRS is upgrading the turbocharger. Replacing the stock turbo with a larger one or adding a second turbo can significantly increase horsepower and torque.

Another popular modification is installing a performance air intake system. This can improve engine airflow and increase power and torque output.

Upgrading the exhaust system is also a common way to improve performance. A high flow catback or turbo-back exhaust can increase horsepower and torque, as well as improve the sound of the engine.