Fort Worth, Texas While their cars look strikingly similar, the Indy Racing League will be able to do something that CART couldn't race at Texas Motor Speedway.
Six weeks after CART canceled a race over concerns about driver safety on the 1 1/2-mile, high-banked track, the IRL has no such fears as it prepares for the Casino Magic 500 on Saturday night.
IRL cars will go about 15-20 mph slower than the 230-plus that caused CART drivers to become dizzy and disoriented during practice, prompting fears they would pass out in the race.
That difference in speed is enough to enable the IRL to race on a track CART deemed too dangerous.
"We certainly don't want to be confused with CART by any stretch of the imagination," said Johnny Rutherford, a three-time Indianapolis 500 winner and CART's 1980 champion who is now a special projects coordinator for the IRL. "The cars look the same, but they're not."
CART's engines are turbocharged, producing more than 800 horsepower. IRL engines are normally aspirated and have a maximum horsepower of about 675.
Billy Boat's 226.979 mph qualifying time in 1998 was the fastest for an IRL car in Texas. However, the IRL has since switched to a slightly smaller engine and pole-sitters since then have been in the 212-215 range.
When CART visited in April, Kenny Brack earned the pole with a qualifying run of 233.447 mph. Four drivers broke 236 in practice.
The combination of high speeds and high banking at Texas caught CART off guard because there had been no full-scale testing. By contrast, IRL will race at Texas for the eighth time in five years.
The banking was an extreme adjustment for CART drivers. The Texas track goes up 24 degrees; no other track CART races on goes above 18 degrees.
The combination of the higher bank and the higher speeds CART drivers reached around the track produced an extreme gravitational pull, known as "G force."
CART officials did not realize the problem until drivers spent nearly four hours on the track over two days of practice. They called off the race just two hours before it was scheduled to start.
Texas Motor Speedway has since sued CART, seeking the $2.1 million sanctioning fees it paid along with millions of dollars lost because of the cancellation. The lawsuit, originally filed May 8 in a county court, has been shifted to a federal district court in Sherman, Texas.
Joe Heitzler, CART's chief executive, and other CART officials haven't commented on the Texas situation since the lawsuit was filed.
CART and IRL vehicles do have much in common, starting with their looks. Both have rear engines, wings on either side of the nose and a wing on the back.
What separates them are a series of technical and aerodynamic specifications, such as varying configurations of those wings.