Tune, intake, exhaust, throttle body, short throw shifter, lightweight aluminum driveshaft, underdrive pullies, forged internals, SC/TC, Camshafts, Nitrous
, Springs, shocks, struts, sway bars, control arms.... The possibilities are endless if you have a deep enough pocket.
---------- Post added at 03:33 PM ---------- Previous post was at 03:32 PM ----------
What is it that you want to focus on? Performance or straight Power?
And how much do you know about Mustangs? (It will help when deciding what to get)