The aftermarket isn't going to respond in a year. Consider what the aftermarket has done for other potent engines of the past. GMs LS engines didn't get exciting until a few years ago. A few YEARS ago. Now, you can build an LSX shortblock, starting in the low $2k range for it, for less than $10k and produce numbers north of 900hp on PUMP GAS.
The question you ask is clear, but your ambitions seem greater than the average joe. Not many people are going to complain about a 4 door sedan north of 4k lbs running 12s. Also, what's the point? You're better off moving on to a much more managable chassis. a CTS-V comes to mind. Already supercharged and basically ready for 10s with a pulley swap and slicks.
I'm not bashing you about this, to be clear. You have to consider that everything about this car is total ******. Drivetrain, Powerplant and chassis. Yes, two of the three are nothing (entirely) new to production, but we're talking total virgins to the modification world. Throw in the threat of potential warranty voids and you'll just have to wait until the powerplants are more mainstream (maybe a mustang although that seems uncertain with the ranks of the 3.7, the pickups and other sport models to share the powerplant) and have more consumers willing to get... CRAZY!
I still have to say... mid 12s out of a vehicle with tons of gadgets and MASSAGING SEATS is flat out impressive... Try doing that 10 years ago!
Our air is getting much better too so I do expect low 13's very soon. With some exhaust work maybe 13.0.
