If you paid attention to Wednesday’s private INDYCAR test at the Indianapolis Motor Speedway or track president J. Douglas Boles’ Twitter account, you would notice that the racing surface is considerably darker than the last time Indy cars roamed the track in August.
Not only is it darker, but the color is a light-devouring jet black that mirrors the appearance of a full-surface repave – though the track hasn’t had any new asphalt laid down since 2004. So why does it appear so?
After NASCAR’s Brickyard 400 was completed in early September, IMS had a compound named recycled polyethylene (RPE) applied to the racing surface that serves as an asphalt binding agent. Essentially, the sealer will protect and strengthen the 14-year-old asphalt as it prepares for another Indiana winter.
So what exactly is recycled polyethylene? You’ll be surprised the substance is now part of the sacred Speedway surface.
Recycled polyethylene is known in Layman’s terms as recycled plastic. The practice of recycling plastic and using it for not only sealing purposes but also full road construction has been in place for years now.
This particular compound will penetrate the IMS racing surface and fill in some foundational fractures in the asphalt as well as mask some of the cosmetic blemishes you may have noticed in May. This includes spots on the track where the Speedway track crew ground down uneven bumps at various points of the 2.5-mile oval, leaving a lighter-than-normal strip of asphalt in multiple locations.
By applying the sealer it also covered up the once-faded grid markers from Formula One’s tenure at the track, though Boles mentioned that they will probably re-appear in a faint form by the spring. The racing surface’s current flat black color is projected to lighten as the winter months roll along, leaving a similar dark grey color that we have grown accustomed to in May.
Ahead of this week’s private INDYCAR test, many wondered whether or not the sealer would affect grip levels as Indy cars traveled at over 220 miles per hour. Boles predicted the sealer would not affect grip rate.
“Grip level (will be) the same,” Boles stated on test day. “Technically, the application penetrates the surface and closes off hairline gaps under the surface to help prolong the life of the asphalt.”
As the full day of testing concluded, series champion Scott Dixon confirmed Boles’ prediction while also praising Firestone for improving on their tire compound used in May 2018.
“The ’19 (tire) is much more consistent, it’s much easier to feel what it’s doing, the grip level is up, which we need mechanical grip,” said Dixon, the driver of the No. 9 PNC Bank Chip Ganassi Racing Honda. “Firestone, to be honest, has done a very, very good job.”
Boles and company have done a great job, as well, to preserve the facility as it continues to age. By applying this sealer it most likely buys the Speedway another year or two before embarking on what will inevitably come – a full surface repave.
The current surface has seen some of the most exciting finishes in the track’s storied history. Here’s to hoping it is around for just a few more memories.
Header image by Chris Owens/INDYCAR.