The heart of the CTS Turbo B8 A4/A5 2.0T turbo upgrade kit is the Borg Warner K04-0064 turbocharger. This turbocharger is commonly used in OEM applications such as the Audi S3 available in Europe. The highlight of this Borg Warner turbocharger in our kit is the 'forged mill' compressor wheel, which brings numerous benefits to the enthusiast. The technology used in the production of these turbos provides us with a variety of benefits, reduced compressor wheel weight (faster spool), increased strength, and greater surface area of the compressor wheel. Because of the 'forged mill' technology Borg Warner can increase the effective surface area of the compressor wheel, which results in greater air flow than conventional cast compressor wheels.