What is the best modification for increasing horsepower in a Toyota GR86?

I just purchased a Toyota GR86 and was wondering what the best modification would be for increasing horsepower without sacrificing reliability. Any suggestions?

Congratulations on your new Toyota GR86! One of the best modifications for increasing horsepower in your car would be to install a cold air intake system. This will allow for better airflow and increased horsepower without sacrificing reliability.

Another option for increasing horsepower in your Toyota GR86 would be to install a performance exhaust system. This will not only add a deeper, more aggressive sound to your car, but also improve exhaust flow and increase horsepower.

Adding a turbocharger or supercharger is also a popular way to increase horsepower in the Toyota GR86. Just make sure to do your research and choose a reputable brand to ensure reliability.