noun
modified car; custom car; remodeled car
Refers to a car that has been altered from its original factory state, often for performance, appearance, or personalization. Common in car enthusiast contexts.
彼は改造車でレースに出場した。
He entered the race with a modified car.
この改造車はエンジンも内装もカスタムされている。
This custom car has both its engine and interior customized.
チューニングカー specifically refers to a car tuned for performance, whereas 改造車 is a broader term that includes aesthetic and functional modifications.
Compound of 改造 (remodeling, modification) and 車 (car). The term is straightforward and modern, with no obscure historical derivation.