What is the best way to increase horsepower in a Ford Focus?

I have a Ford Focus and I want to increase its horsepower. I've read about different methods like adding a cold air intake, installing a performance chip, and upgrading the exhaust system. Which one is the most effective and affordable option?

I recommend adding a cold air intake to your Ford Focus. It's a cost-effective way to increase horsepower. You can also consider installing a performance chip for an additional boost.

Upgrading your exhaust system can make a significant difference in horsepower, but it can be expensive. You may want to start with a cold air intake and see if that provides enough of an increase for your needs.