Originally Posted by MarkyMark
I just got 3.73s put in and I didn't feel much of a difference. Is the tune only for Speedo calibration or does it help the performance also?
I'm sorry to hear you the gears didn't wake the car up as much as you expected. Like others have said, the jump for 3.31 to 3.73 is not a huge difference, but it should still be noticeable.
The tune for the most part is mainly to correct speedometer and odometer readings, unless you have an auto, in which some shift points are sometimes changed as well, but still a minor change.
I'm confident that the car is much quicker and if you took it to the track, I think you would really see the benefits. Often times it is hard to feel the changes, and but when taken to the track you will see the pick ups.
I hope this information clears some things up, if you have any questions feel free to get back in touch. Best of luck!