A car modified to increase its speed and acceleration WordNet 3.0 & Open English WordNet

Hot rods are typically American cars that might be old, classic, or modern and that have been rebuilt or modified with large engines optimized for speed and acceleration. Wikipedia

Typically American car with a large engine modified for linear speed. Wikipedia Disambiguation

Typically a passenger vehicle modified to run and/or accelerate faster. The term may be used generically to apply to any car, truck, or motorcycle (et al.) modified for increased speed and/or performance. It may also be used to specifically describe and refer to modified cars from the original (or traditional) era of "hot rods", post World War II and prior to 1960. Wiktionary