Review for LEGO set 6337 Fast Track Finish from Brickipedia
“The F1 racing cars have the numbers "1" and "3". Number "2", "5" and "6" were included in 6335 Indy Transport and number "4" in 6546 Slick Racer. These six racers shared a common design and were all released in 1996.”
Full review at brickipedia.fandom.com