Facing a tough economy and fan complaints of boring racing, NASCAR had made several rule changes, which were announced at a press conference Thursday, January 21, 2010. The changes, which span across all three series, are slated for the 2010 season.
One of the biggest changes, which has already been made public, is the transition from a rear wing to a spoiler  in the Sprint Cup Series. NASCAR instituted the rear wing as it transitioned to the Car Of Tomorrow back in 2007. It was said to be safer, and I think generally, it has been. But, fan acceptance never grew.
A car with a rear wing looks much less like the street version of the car. With carmakers struggling so much – and possibly having to justify their participation in NASCAR – it is no surprise NASCAR is working towards making the cars look more like their street counterparts. Thus, the old saying, “Win on Sunday, sell on Monday,” becomes a little more true.
NASCAR evaluated the wing, and put it in for “all the right reasons,” according to NASCAR President Mike Helton. But, support for the wing didn’t increase to the level anybody “thought it should.” So, NASCAR opted to change back to a spoiler. It should add more balance to the car, make it more drivable, and create better racing. Thus far, reviews have been positive.
NASCAR Chairman and CEO Brian France added that they hope to have the spoiler ready for debut at a superspeedway by the Texas race in April. It should be ready for tracks smaller than 1.5-mile tracks earlier than that.
Brian France said there was “nothing to report” on whether or not the front end of the COT will change. Helton added that a factor in not changing the front of this car at this time is that they didn’t want to release too many changes for the owners to deal with at one time. The current car features a splitter on the front.
The yellow line rule at plate tracks, which was expected to go away, will in fact stay, “for now,” according to NASCAR’s Vice President of Competition Robin Pemberton. At this time, NASCAR determined that the rule needed to stay. But, Pemberton said that they will consider changing the rule at a later date. (I’m not sure if it should be changed .)
NASCAR also plans to use a larger restrictor plate, the biggest since 1989. The reasoning is that things that were added to the car to improve stability also created drag. So, NASCAR is moving to a larger plate to give power and responsiveness back to the car to offset the increased drag.
The Nationwide Series will introduce its Car Of Tomorrow  in 2010. The car is slated to appear in four races, Daytona in July, Michigan, Richmond, and Charlotte. Crews will also be limited in the series in 2010. Crews will now be made up of 15 members, including a driver, a crew chief, a spotter, and seven over-the-wall members. And, N’Wide teams cannot run more than two races without using engines sealed by NASCAR.
In the Camping World Truck Series, double-file, shootout style restarts  will debut in 2010. Double-file restarts are already in place in the Sprint Cup and Nationwide Series. In addition, the truck series will move back to conventional style pit stops.
In 2009, rules prevented teams from taking tires and fuel in the same pit stop. This was an effort by NASCAR to save money. Now, teams can take both during the same stop. Also, truck teams can use a self-venting fuel dump, which will eliminate the need of a catch can.
Update: NASCAR has added a list of banned substances to the 2010 rulebook. The governing body also included its entire drug policy in the 2010 rulebook, for clarity. This comes in response to many complaints that followed the Jeremy Mayfield incident .