The unique Bell helmet to mark the occasion has been created by Kostecki's long-term designer, Gold Coast-based Antman Helmet Design
“I've worn Bell my whole Supercars career, so yeah, they've been a part of me for a while now and gave me a helmet to do this, which is really cool,” Kostecki told Speedcafe.
“I get Antman to do all of my helmets, and I said I want something special for this.
“He really hit it off and incorporated MobileX in there, with the green, and some history of Indy as well in the background of the helmet.”
In place of the standard white base and Boost Mobile orange of his Supercars lid, Kostecki's NASCAR helmet features a greywash of Indianapolis history surrounded by green highlights.
On the top, it includes the first Indianapolis 500 winner, Ray Harroun, who won the now iconic event in 1911.
Kostecki says that he does not have any plans for what he'll do with the one-off helmet post-event.
“I haven't really thought about that to be honest. I'll see what happens and see if it means anything to me afterwards.”
As well as RCR team-mates Kyle Busch and Austin Dillion, Kostecki will have a familiar sparring partner in Sundays Cup Series race in fellow Supercars competitor, Shane van Gisbergen.
Van Gisbergen will make his second NASCAR Cup Series start after a stunning debut win for Trackhouse Racing on the streets of Chicago in July.
The New Zealander will also field the #41 Niece Motorsports Truck entry in his NASCAR oval debut in the lead up to Sunday's Cup Series race.
Fittingly, Kostecki and van Gisbergen were the two winners at last weekend's Supercars round, with Kostecki winning Saturday night's Race 18 while Van Gisbergen took the Sunday afternoon win.