How much horsepower does a 4.2 Vortec have?
The 4.2-liter Vortec inline-6 typically produces about 270–275 horsepower, with torque around 275–285 lb-ft, depending on the year and configuration.
The 4.2 L Vortec is GM’s inline-6 engine used in a range of mid-2000s SUVs and light trucks. It powered models like the Chevrolet TrailBlazer, GMC Envoy, Buick Rainier, and Saab 9-7X in various markets, with small variations in output due to emission rules and calibration.
What is the 4.2 Vortec?
The 4.2 L Vortec is a GM straight-six engine that formed part of the company’s Vortec family. It was deployed primarily in mid-size SUVs and trucks during the early to late 2000s and was paired with automatic transmissions in several GM-branded vehicles.
Power figures by year and model
Below is a concise breakdown of typical horsepower figures reported for the 4.2 L Vortec inline-6 in common GM applications. Note that emission packages, transmissions, and tuning can influence the exact figure.
- 2002–2003: about 270 horsepower; torque around 275 lb-ft
- 2004–2005: about 275 horsepower; torque around 275–280 lb-ft
- 2006–2009: about 275 horsepower; torque around 275–285 lb-ft
These numbers reflect SAE net horsepower as typically cited in official specifications. Real-world output can vary with altitude, gearing, and vehicle condition.
What factors can cause horsepower numbers to vary?
Because the engine’s output depends on calibration, exhaust and intake tuning, emissions equipment, and other variables, horsepower figures are approximate and can shift by a few horsepower across model years and markets.
Summary
In practical terms, the 4.2 L Vortec inline-6 delivers roughly 270–275 horsepower, with torque typically in the 275–285 lb-ft range. While exact numbers vary by year and configuration, the engine maintains a narrow power band across its common GM applications.
