What is the biggest four cylinder motor made by Chevrolet?

The largest four-cylinder engine Chevrolet ever mass-produced for a passenger car was the 2.8-liter inline-four (often referred to as the 2.8L "Iron Duke") found in various models, notably some early S-10 pickups. While other larger four-cylinder engines might exist as prototypes or in very limited production, the 2.8L Iron Duke holds the title for the biggest widely available four-cylinder Chevy passenger car engine.