* GT: The GT model typically had around 260 horsepower.
* Other models (base, V6, etc.): These models had significantly less horsepower, typically using a smaller engine. The 4.6L was primarily in the GT.
So, while a 4.6L *usually* means a GT with around 260 hp, you need to specify the *trim level* of the Mustang to get a precise answer.