got my 4.10s installed today, its a tottally different car now, instant responce, really like the full throttle off line, hold it and when 2nd gear hits it chrips the tires pretty good, before with the 3.27s i got just a little bit, its never gonna see the track, just a fun sunny day cruiser, very happy. had it since new, never gonna sell it, been looking at the new shelby 550 turbo, it looks like the ultimate mustang. looks like the right way to go if you want really fast mustang.