But her moment of glory still seemed "unreal", Hay said.
It topped the births of son Troy, 15, and daughter, Bree, 13.
"I mean, we'd been trying to do this for five years."
Hay's father, Lindsay, 65, runs his own concreting business in Rotorua and has spent late nights on the twin turbocharged 7.9-litre big-block Chev V8 engined '27 Ford T Roadster-bodied car. He bought it for himself, but stepped away so his daughter could reach her dreams.
Her success was because of, and for, her dad, Hay said. "He works his guts out on that car. it was so emotional [after the race]. As soon as we saw each other, we were just bawling. I wanted to do it for him."
Hay's life as a busy mum, wife and bank worker couldn't be more different from her hobby. And that's just how she likes it.
"I think it's always good to do something that's not the norm. And beating the boys is good fun."
Daughter Bree is a junior dragster, and already has her eye on mum's record, Hay said.
"I think it would be cool. But her grandfather has to live long enough to do the engine."