There are two automotive phenomena in play with today's ride: The Indy 500 Pace Car, and the Indy 500 Official Car.
First, there's the Pace Car. Pace Cars have mostly been convertibles, but more importantly, the Pace Car needed to be able to be able to perform the chores of the actual pace car in the race. During the Malaise Era, this resulted in actual Pace Cars that were heavily modified to be up to the high speeds involved, and those modifications were not applied to the replica Pace Cars sold for the street. As an example, the actual '83 Riviera convertible Pace Cars for the track (there were two built) had 4.3L twin-turbo intercooled V-6 motors that pumped out more than 400 horsepower and were in no way remotely street legal.
Then there are the Official Cars, which are used in 500 Festival events and parades leading up to the race and in the festivities on race day. Frequently these are the same make and model as the Pace Car, but not necessarily. In 1983, they were, though: Riviera convertibles.
This one was snapped in September of 2024 using an Olympus OM-D E-M1X and Panasonic 12-60mm f/2.8-4 zoom lens.