I've been thinking...

[DirtyD]

I say keep it. If you want a little more speed, maybe go with a centri s/c with a small amount of boost to have some fun.

Or save up, wait until the next gen Stang, preferably the 2016 year model so they can work out the kinks from the new chassis, and reap the benefits or waiting.

You can whip some Sentra ass then!