What is the most efficient oil to use for an Audi 80?

I want to make sure I am using the best quality oil for my Audi 80 to ensure optimal performance and longevity.

For Audi 80s, it's recommended to use fully synthetic oil with a minimum viscosity rating of 5W-30. This will protect and lubricate the engine better, especially during cold starts.

If you want an even better performance, consider using a high-performance oil like Mobil 1 or Castrol EDGE. These are specifically designed for high-end vehicles like the Audi 80 and will provide increased protection and performance.