The Ls2 in the SS people have already gotten down to 10 secs or so, what would be the point of a V12 lol, its like saying im going to stuff the biggest engine i can think of and the biggest turbo and expect so much power. I mean hell, you could always go whacky and do turbos off of each runner.... why the hell not right??
I mean there are other things you need to take into consideration when you are doing that.... Any LS Series engine is a perfect fit and fine on its own

and obviously cheaper in the long run