* 2.8L V6: This was the standard engine for the RS. It produced 135 horsepower and 160 lb-ft of torque.
* 3.1L V6: This was an optional engine for the RS and produced 160 horsepower and 185 lb-ft of torque.
* 5.0L V8: While not standard, a 5.0L V8 was an option for the RS. This engine produced 220 horsepower and 275 lb-ft of torque.
To determine the specific engine in your 1990 Camaro RS, you'll need to check the vehicle identification number (VIN) or consult the owner's manual.