On January 12, 2006, NASCAR announced a universal car named "Car of Tomorrow" or (COT for short) after a five-year design program sparked by Dale Earnhardt's crash during the 2001 Daytona 500. The primary design considerations are "safety innovations, performance and competition, and cost efficiency for teams." 
All cars were required to fit the same set of templates. NASCAR uses 4 different manufacturer Models: Ford Fusion, Chevrolet Impala, Dodge Charger, and Toyota Camry. NASCAR has frequently adjusted the rules to ensure that different car manufacturers have relatively equal cars. The universal body of the Car of Tomorrow will eliminate these problems.
The car reduced dependence on aerodynamics and improved handling. The car featured a detachable wing, which had not been used since the Dodge Charger Daytona and Plymouth Superbird in the 1970s.  However, in early 2010, the wing was replaced with the traditional spoiler. The COT also had a splitter until 2011, until it was redesigned. The windshield is more upright, which increases drag. The air intake is below the front bumper of the car, which eliminates overheating caused by clogged grills. The front bumper is more box-like, which slows the car down by catching more air.
The Car of Tomorrow improved safety features over the current car. The driver's seat has been moved four inches to the right, the roll cage has been shifted three inches to the rear, and the car is two inches taller and four inches wider. More "crush-ability" is built into the car on both sides, ensuring even more protection. The car's exhaust runs through the body, and exits on the right side, which diverts heat away from the driver. The fuel cell is stronger, and has a smaller capacity 17.5 gallons from 22 gallons.
The Car of Tomorrow was first tested at the 2.5 mile Daytona International Speedway, then on NASCAR's two shortest tracks, Bristol (0.533 mi) and Martinsville (0.526 mi.), the 1.5 mile Lowe's Motor Speedway outside Charlotte, North Carolina, and Michigan. Former NASCAR driver and NASCAR Director of Cost Research Brett Bodine has tested the prototype car against cars prepared by current NASCAR teams.
The Car of Tomorrow was first raced at the 2007 spring race at Bristol Motor Speedway. The car would be used at sixteen more events in 2007, consisting of all tracks less than a mile and a half in length, the road courses, and the second Talladega race. In 2008, the Car of Tomorrow was expected to be only added to two more tracks however due to the success of the 2007 events, NASCAR announced that it would compete in all of the races in the 2008 season. The car would prove success in all events for 2008 and would make a return in 2009. In 2010 the Car of Tomorrow raced another full season and continued to be raced in 2011. However it was announced that a new Generation 6 car would make its debut in the 2013 Daytona 500 and at the 2012 event at Homestead International Speedway, the Car of Tomorrow made its final appearance in Sprint Cup competition.
- ↑ http://www.nascar.com/2006/news/headlines/cup/04/04/cot_martinsville/index.html
- ↑ http://www.truckseries.com/cgi-script/NCTS_06/articles/000061/006135.htm