The Hendrick Motorsports machine was almost four seconds faster than the quickest GTE Am entry in Wednesday's opening qualifying session, despite the team's modest pre-event public predictions of being somewhere in the middle of the GTE Am pack.
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Instead, 2010 Le Mans winner Mike Rockenfeller posted a 3m47.976s lap that was only 8.5s slower than the lowest-ranked of the LMP2s.
"I think we've progressed a lot and here we are qualifying four seconds quicker than all the GTE cars - I think it's a phenomenal effort by the whole team," said Button.
"We came here thinking we'd be in the mix and, when the GTE cars get the amateur drivers in the car, we'd be able to be as quick as them - if not quicker - but we didn't expect to qualify four seconds in front of the quickest GTE car.
"Everything has been spot on, all the homework that's been done by this team has been phenomenal and I would put it up there with one of the best teams I've raced with in the world."
Source: Autosport