As for top speed, a stock 1988 Thunderbird 5.0 wouldn't likely exceed 125-135 mph. Several factors influence actual top speed, including:
* Condition of the vehicle: A well-maintained car will perform better than one that's neglected.
* Gear ratios: Slight variations in gearing can affect top speed.
* Aerodynamics: Things like aftermarket spoilers or even just tire pressure can impact aerodynamic drag.
* Road conditions and elevation: Headwinds and uphill gradients will significantly reduce top speed.
* Driver skill: Aggressive driving techniques and poor vehicle control can impede top speed.
It's important to remember that exceeding posted speed limits is dangerous and illegal.