The L83 truck engine runs a belt driven mechanical vacuum pump in order to generate vacuum for the brake booster. The C7 Corvette will likely get an electric pump. I assume the Camaro will also go electric.
Here is an image of the pump (attached to the block on the driver side low in the accessory drive):
Image of vacuum line that goes from the pump to the brake booster:
http://www.lingenfelter.com/LPEforum...0&d=1371590957