Green’s Dictionary of Slang

(US) one who drives a customized ‘hot rod’.

1959		H. Ellison ‘No Game for Children’ in Gentleman Junkie (1961) 76: He occasionally ran with a clique of rodders known as the Throttle-Boppers.
1975		H. Ellison ‘Along the Scenic Route’ in Deathbird Stories (1978) 45: George, you’re a family man, not a rodder!
2018		T. Pluck ‘Hot Rod Heart’ in Life During Wartime 103: They pulled over at Rutt’s Hut, a brick shack that [...] served as the local cruise spot. A few rodders already held court.