Finding a car with 400 hp under $10k can be a challenging task, but there are options available. Some potential choices include older muscle cars such as the Ford Mustang GT, Chevrolet Camaro SS, or Dodge Charger R/T from the mid-2000s. Additionally, sporty models like the Pontiac G8 GT or Chrysler 300C with a HEMI V8 engine could also meet the criteria.

It is crucial to conduct thorough research, perform inspections, and consider potential maintenance costs when exploring high-performance vehicles within this price range.