Chevrolet’s new Corvette ZR1 bowed with an incredible 755 horsepower and 715 pound-feet of torque last month with a noteworthy engine under the car’s shaker hood: a 6.2-liter supercharged LT5 V8 engine. Like most awesome projects, the new LT5 engine had a special code name to ensure others didn’t know what exactly was in the works.
That name was “BAS.” What is BAS? Jordan Lee, chief engineer of the new LT5, shed some light on the name in an Automotive News (subscription required) report published Tuesday. Instead of stamping “LT5” or “Corvette ZR1” on the top of the engine, the “BAS” code name made its debut. The code name has two meanings, per Lee: First, “BAS” actually stands for “belt alternator system,” which is something General Motors uses in a diesel engine. That’s what the engineers wanted others to believe it was.
Second, and most importanly, engineers gave BAS a different meaning: big ass supercharger. We don’t kid.
It’s a fitting nickname. The 2019 Corvette ZR1’s supercharger is 52 percent larger than the unit fixed to the Corvette Z06’s LT4 V8 engine and helps kick power well past the 700 hp mark. Lee also said the supercharger actually spins slower than the LT4’s to produce less heat at 15,860 rpm versus 21,000 rpm in the LT4. And the new supercharger needs a lot of power to ensure it runs—110 hp, to be exact.
Engineers fitted an 11-rib belt to fulfill the need for extra energy needed to spin the supercharger. At the end of the day, the LT5 is actually making 865 hp before the supercharger sucks some power away.