How much HP does a stock 5.7 350 have?
The stock horsepower of a 5.7-liter Chevrolet V8 (the 350) is not a single figure; it varies by variant and year. In general, stock numbers range from about 255 hp in the 5.7L Vortec variants to around 350 hp in the late-1990s LT1/LS1 performance versions.
Context: the 5.7L 350 family and why numbers vary
The 5.7L (350 cu in) small-block has been produced in several generations and configurations, from early carbureted setups to modern fuel-injected versions. Each variant received different tuning, compression, and gear ratios, which means the factory horsepower changed over time and across applications (trucks, sports cars, and performance models). If you want the exact number for a specific vehicle, you’ll need to identify the exact model-year variant and consult the original specification.
Common stock variants (approximate horsepower)
Below are representative ranges for the major factory variants people refer to when they talk about a “5.7 350.” Exact figures can vary by year, market, and equipment.
- 5.7L Vortec 5700 (Gen I; used in trucks/SUVs in the late 1990s): about 255 hp (roughly 330 lb-ft of torque).
- LT1 family (Gen I; used in Corvette C4 and F-body cars in the 1990s): roughly 275–330+ hp depending on year and tuning.
- LS1/late-gen 5.7 variants (late 1990s–early 2000s; Corvette C5 era and related applications): typically about 305–350 hp in stock form.
In short, the horsepower for a stock 5.7L 350 depends on which variant you have and the year it was produced. If you can specify the exact model and year, I can give you the precise factory rating.
How to verify the exact horsepower for your vehicle
To determine the precise stock horsepower for a specific car or truck, use these steps:
- Check the original window sticker or build sheet, which lists the factory horsepower.
- Look up the VIN-decoded specifications from GM’s official resources or reputable archives; the engine code and horsepower are usually listed.
- Consult the owner's manual or service manual for the engine variant; some models have published horsepower figures per year.
- If you have access to the vehicle, a chassis or engine dyno can verify baseline horsepower, though results can vary due to testing conditions (still useful for confirmation).
- Ask a dealer or well-informed Chevy enthusiasts forum with your exact year and model to confirm the correct figure.
Bottom line: the precise horsepower is defined by year, model, and calibration. Once you identify the exact variant, you can confirm the official figure from documentation.
Summary
The stock horsepower of a 5.7L Chevrolet 350 varies widely by variant and year. Typical ranges span from about 255 hp in the Vortec-equipped trucks to around 305–350 hp in later LT1/LS1 performance versions. For an exact figure, determine the specific engine variant and year, then consult the original documentation or reliable spec sources.
