What is the best way to increase horsepower in a Audi 80?

I recently purchased a used Audi 80 and I'm looking to increase its horsepower. What is the most effective and safe way to do this?

Upgrading the air intake and exhaust systems can give you a significant boost in horsepower. Make sure to choose high-quality components for maximum results.

Adding a performance chip or tuning the engine can also increase horsepower, but be sure to research and find a reputable company to avoid damaging your engine.

Consider investing in a turbo or supercharger kit for a major boost in horsepower, but be aware that this can be a more costly and complex process.