* Specific Model: A high-performance Ford Mustang Shelby GT500 will be significantly faster than a Chevy Spark. Conversely, a Chevy Corvette Z06 will likely outperform a Ford Fiesta.
* Year: Performance specs change from year to year within the same model.
* Engine: Different engines within the same model (e.g., a V6 vs. a V8) will have drastically different performance.
* Modifications: Aftermarket modifications can significantly impact a vehicle's speed.
To compare speed, you need to specify the exact make, model, year, and engine of both the Ford and the Chevy you're interested in.