I dont think you can just throw a 16 volt batt in the front, it could fry the cars computer, which would not be too good. It also would not charge with the stock alt. Maybe if you ran dual alts you could have a regular stock alt and a 16v alt for all of your batts not associated with the other things in the car, and the stock alt for the batt up front and the cars other accessories. This is all if you havent already accomidated for this and if youre replacing the front batt with a normal 12v batt.
Also dont quote me on this Im just assuming.
EDIT: Chevy beat me to it.