You are looking at approx. 3000 lbs on a contour (this all depends on trim level and other factors) The more heavily modified 3l's are hitting low 14's in the quarter (this includes a lsd and a nice clutch amoung other things) If you had an lsd as well as a good clutch then I wouldn't be suprised by mid to high 13's. With spray I'd guess mid 13's. High 12's in my own opinion is a bit of a pipe dream with this type of setup. Traction will end up being a big issue.
Oh ya, I wouldn't make anymore 4 door's are slower comments. We might be a bit touchy on here...
We do after all drive four door cars.
LOL.
