NASCAR Tweaks rules to limit drafting

NASCAR officials announced two technical changes Sunday evening aimed at preventing the sustained two-car drafts that dominated Saturday night's Budweiser Shootout at Daytona. Robin Pemberton, NASCAR's vice president of competition, said the body issued a bulletin to race teams with the following specifications:

" The maximum size for the air inlet for the cooling system will be 2½ inches tall by 20 inches wide.
" The pressure release valve on the water system will be set at 33 pounds per square inch.

The intent is to set up the cars so they can't push each other in two-car tandems for extended runs without overheating. Teams try to line up drafting partners at Daytona and Talladega so they can overcome the limitations of the restrictor plates used to keep speeds down at those two tracks. "That will bring down the temperatures so the teams can't run at 290 or 300 degrees [without overheating] on the extended push of 30 or 40 laps," Pemberton said.

"This will put [the water temperature in the engines] back in the 250-degree range."

Several drivers, crew chiefs and team executives expected NASCAR to control the pressure relief valve. Jamie McMurray, who finished second to Kurt Busch in the Shootout, said many cars had valves that allowed the temperature up to 300 degrees before boiling over. That allowed the second car in the two-car draft to push longer without overheating — some for more than a dozen laps — under Saturday's cooler outdoor temperatures. The weather is expected to be warmer for Thursday's qualifying races and the Daytona 500. More at ESPN.com