How much horsepower and torque did a stock 1997 Chevy 5.7l engine put out?

The stock 1997 Chevy 5.7L engine, depending on the specific application (truck, van, etc.), produced somewhere in the range of 250-280 horsepower and 325-350 lb-ft of torque. There wasn't a single number across all vehicles using that engine. You'd need to know the exact model of the vehicle (e.g., Silverado, Tahoe, Suburban) to get the precise factory ratings.