Added the 4.10s to my car today. I have an 07 gt manual(5spd), I have 18 inch bullitt rims, have 255s on the front and 275 on the back. Bridgestone sport potenzas.. have a CAI, and diablosport tuner chip. My car had the stock 3.55s in it. It would pull okay, but you almost had to burn clutch in 1st n 2nd gears to keep rpms high enough to help where the car was lacking.. not anymore! The 4.10s with the work I mentioned wake it up so well.. I promise u will never look back if u add these. Makes the car night and day differences.. don't know the time difference but I honestly feel like without embellishing too much that my 0-75 time is what the car stock was 0-60. It's that much dif in power! Also I have traction control disabled as well as the rev limiter banged up to 6950. I have never spun my tires unless I meant to if the road was dry since having the "real" tirews on the car and not the puny stock crap.. also meant to mention I do have an h pipe and bassani exhaust as well.