However, it's important to note:
* Year Matters: Specific performance varies significantly between model years for both cars. A newer Mustang GT might have performance upgrades that close the gap or even surpass an older SS.
* Modifications: Aftermarket modifications can drastically alter performance in either car. A heavily modified Mustang GT could easily outperform a stock SS, and vice-versa.
* Driver Skill: Driver skill plays a huge role in overall race times.
In short, while a stock Chevy SS usually holds a performance edge over a stock Mustang GT, the specifics depend heavily on the model year and any modifications made to the vehicles.