But there wasn't enough time left to cause overheating, and if anything, the tape made his car even stronger by nailing down the front end even better aerodynamically.
And this year's bad luck fell to Hamlin, who had to run to the end without radio contact with his spotter.
"Our radios got wet after the rain," Hamlin said. "I was trying to spot for myself at the end of the race. It's hard to win a superspeedway [restrictor-plate] race when you don't know when runs are coming, when you have to time your passes ... when you're trying to guard against causing a wreck, knowing you've got radio silence."
Hamlin had won the Sprint Unlimited bonus race here eight days ago, and then won his 150-mile qualifying race Thursday night.
But, "I think our performance declined a little bit as Speedweeks went on by," Hamlin said. "I think the competition got a little bit better and worked on their cars [during practices after Thursday]."
"That car I drove tonight -- we got along," Earnhardt said.
And now, "Monday will be a fun day for a lot of people in Junior Nation," he acknowledged.
Said his team owner, Rick Hendrick, "It doesn't hurt to have the most popular driver win the biggest race in the sport."
How much weight came off Earnhardt's shoulders?
"It's not a weight when you're able to deliver," he said. "It's a weight when you're not able to deliver -- when people say you're the face of the sport and you're running fifth or 10th every week ... "
"And so," he said, "this brings me a lot of joy."