Just a y is not going to net a tenth in 1/4 mile time, is it? I don't own a Contour so I wouldn't know (Mazda6.) But it seems to me with stock manifolds and exhaust, a new y won't do anything.
BTW, I've gotten a 15 flat with a 2.5 60ft before.........in the 6! I'm sure different gearing and power had something to with that though.
