How much horsepower does a 1997 454 vortec have?

The horsepower of a 1997 454 Vortec engine varied depending on the application (truck, boat, etc.) and specific configuration. There's no single answer. You'll need to find the specific engine code or look up the horsepower rating in the vehicle's documentation or a parts catalog specific to that vehicle's year and model. However, a common range for a 454 Vortec in trucks at that time would be between 230 and 290 horsepower.