I do not believe a 12 second streetable six cylinder Chevy II is not unreasonable. Nitrous on a fairly "normal" hot rodded 250 could do it and still be very streetable. Forced induction would probably be better, but the complexity and engineering required does go up. My Chevy IIs have not been real quick due to going old school with plain old carburetion.
I doubt anyone here will deny that $$/HP is higher on an inline than a V motor, but the HP to get in the 12s with enough money or personal ability is not out of reality.
