Roadster

Of the 106 Indy cars that Frank Kurtis built, this Kurtis Indianapolis Roadster D-A Lubricant Special Car #7 is the only one with the unique 'Dubonnet' trailing arm independent front suspension fabricated in 1958. The Kurtis qualified at 142.908 miles per hour and started in the 22nd position. The car was involved in a serious accident on the first lap though Jonney Thompson was able to continue for 51 laps with bent front suspension and tire wear affecting handling. In 1959, driven by Duane Carter, the car completed the 500, finishing 7th; and in 1960, being driven by Don Freeland, the car was withdrawn in lap 129 (placing 21st). The engine is an Offenhauser.

At the 1958 Indy 500, when the D-A Lubricant No. 7's crew chief Roy Sherman took delivery for testing and qualifying, very little was understood by American racing mechanics about tuning an independent front suspension. The driver, Johnny Thomson (one of the best in the era), at first did not like the car since the inside front wheel did not lift off the ground as he was used to in all other cars he had driven. After getting comfortable with the car, he qualified at 142.908 mph and started 22nd. The car was involved in the first lap crash that killed Pat O'Conner. Thomson continued for 51 more laps, but the front suspension had been bent and tire wear and handling were affected.

This Kurtis Indy Roadster was restored in 2007 by Ron Fournier in Shelby Township, MI. It received a complete 'race car rebuilt' to the 1958 D-A Lubricant configuration so that it is now safe for track use as a modern vintage race car. All safety subsystems have been discreetly installed and the roll bar can be removed for show presentation since the 1958 car was not equipped with a roll bar.