The 2009 Formula One world champion is driving a special NASCAR entry at the Sarthe circuit with seven-times Cup champion Jimmie Johnson and former 24 Hours of Le Mans winner Mike Rockenfeller.
The trio share a modified Hendrick Motorsports Next Gen Chevrolet Camaro ZL1 stock car as a 'Garage 56' entry highlighting future technology.
Button, who made his NASCAR debut in March, said the car would not be taking anyone by surprise.
"It sounds even louder than a Cup car. That's what's going to blow people away. You'll be able to hear the car coming from a mile off. It is so loud," he told reporters recently.
"I've actually had different earplugs made to take the noise of the engine.
"It's that low rumble of a V8 that's pretty awesome. It will make you smile. If you're out on track and you hear it come past, it will make you smile. It will also make you smile because it's so big compared to everything else that's racing out there.
"People will just hear it. The sound of it will blow their minds."
The NASCAR entry is not competing for any class win - although given they are one of a kind it will feel like a win if they finish -- but are there to mark the 75th anniversary of the US stock car series.
They already won their first battle on Tuesday, with the mechanics beating all the GTE teams in a pitstop challenge, despite being the only ones using a manual jack to raise the car.
Button described the Chevrolet as a stock car on steroids, removed from those around it on the track but definitely not too quick.
Some of the high speed corners will be a handful, the Briton added, but he hoped to be able to race towards the middle of the pack.
"We don't want to get in the way of people's races but we're still there to perform, still there to finish and as high up as we possibly can," he said.
The Hendrick Motorsports team were nearly four seconds faster than the top GTE Am car in Wednesday's first qualifying and 37th of 62 entries.
