It depends what type of cars: rallycross, rally or trailblazer.
But generally the Ford Escort Mark II is the fastest.
Suzuki Escudo Dirt Trial Car 987 Horsepower
RX 2-stroke
A KTM 250sx is the worlds fastest 250 2 stroke dirtbike.
i think is dirt's.
no bob the builders truck is fastest
no kawasaki is the fastest as i know
you
ktm
Yamaha
mrfq400
Francesco Bernoulli
Lightning Wolver