Exhaust, ride height top NASCAR's worry with COT

MARTINSVILLE, Va. -- Brian Vickers suffered burns on his feet and backside. Denny Hamlin has been battling headaches. Matt Kenseth has felt sick all week.

The Car of Tomorrow is supposed to be the safest vehicle ever used in NASCAR, with a larger cockpit area and side panels lined with energy-absorbing foam. But some drivers were exposed to dangerous carbon monoxide fumes when their exhaust systems failed in last week's debut at Bristol, Tenn., forcing crews to scramble to rectify the problem before Sunday's event at Martinsville Speedway.

It's the most obvious tweak to the COT, which enters its second week after receiving mixed reviews from drivers and cautious praise from NASCAR for its performance last week in Bristol. Officials liked the way the front end held up in competition, the relatively small difference in qualifying times from first to last, and the presence of some smaller teams in the top 20.

But they're also shifting 50 additional pounds to the right side of the cars to alleviate a sticking point the majority of the teams ran across in inspection. They're working on minimum and maximum height procedures. And they're trying to rectify exhaust systems that failed at Bristol and made some drivers sick.

"The exhaust, I think, is the first thing everybody went to work the hardest on, because there were probably more exhaust failures than what we know we need to see," said Nextel Cup director John Darby. "So in just a week's time walking through the garage and looking at the cars [Thursday], tailpipe configurations and the material that they're constructed out of has changed dramatically."

Carbon monoxide is noxious stuff -- driver Rick Mast was forced to retire in 2003 after poisoning from the fumes left him nauseous, ill and unable to withstand exhaust of any type. Vickers suffered minor burns and carbon monoxide inhalation halfway through last week's race after a piece of exhaust tube near the front of the car broke off, crew chief Doug Richert said. Hamlin suffered a cracked exhaust pipe in practice, and began suffering from headaches late in the race even through the damage had been repaired prior to the event.

"We can't directly relate it to carbon monoxide. We thought maybe it was a possibility, given that I picked up a real bad headache halfway or three-quarters of the way through the race," Hamlin said. "... But Bristol has always been bad anyway. Because you're inside of a bowl, you've got all the exhaust from the cars running, all the generators from the tractor trailers running during the race, nothing can escape. It's all inside the bowl right there." (Continued)