The LFX Motor
The LFX is Chevy's "High Feature" 3.6L 60° V6 DOHC all-aluminum engine found in several different specs across the 2012-2014 Chevy and Cadillac line-up. It is packed with tech; direct injection, variable valve timing, a composite intake manifold to reduce weight, timing chain (not a belt), and an integrated exhaust manifold head design that collects exhaust gas into one single exhaust port on each side of the engine (in other words, a dream to fabricate exhaust for this).
Although found in the Cadillac CTS, ATS, Chevy Impala and others, the one to get is from the Camaro. Rated at 323hp and 278 ft-lbs at the flywheel.
The fuel system's hardware is all designed to be E85-capable, with injectors sized at 109 lbs/hr (1,100cc). So switching to E85 is just a tune away - no hardware changes needed.