your car being a 4door is the least of your problem, because like pdiggs said there's not much of a weight difference.
put on a greddy kit and adjust it to 8 psi and boom your in the 14 second club.... you can't just bolt on a turbo and expect to be in a certain 1/4 mile time because there are tons of factors that are involved, such as driving skills, amount of boost your running, track condition, you get my point.
if you want real life proofs visit my post about my 1/4 mile times...
http://hstuners.com/forums/showthrea...threadid=21964