Engine problems lead to 43rd-place finish for Burton (cont'd)

Despite the fact Burton's already won this season, Johnson scored his fourth victory, giving him the going-into-the-Chase advantage, if the status quo maintains.

Burton finished second in the first Car of Tomorrow race, and then sixth and 13th in the other two, so that added to his expectations of at least contending for the win Sunday.

After he changed clothes and emerged from his hauler, Burton was asked the source of his frustration.

"That's a pretty stupid question," the usually level-headed Virginian snapped. "You have a good car and I'm sitting here going to finish dead last [so why I'm frustrated] that's pretty obvious."

RCR's assistant head engine builder Danny Lawrence said Burton's engine suffered a broken valve and, even though Lawrence was worried a valve train problem that affected the engines in two of three RCR cars last fall at Dover might recur, it didn't as Kevin Harvick finished seventh and Clint Bowyer, ninth.

"When we get [Burton's engine] back to the shop we'll look at everything, but the head of the valve broke off and it goes through the engine and creates a lot of damage -- that's why we can't keep running it," Lawrence said. "The other cars all have the same parts and generally when something like this happens, it's a parts failure.

"We'll just have to see on the other cars, but you're always concerned because it's the same parts."

Burton knew while his engine was running, it was a good piece.

"The Lenox Chevrolet was 20 laps into a run and the car was really fast," Burton said. "We were marching up through there nicely [then] I broke the engine -- I don't know why.

"We were only turning like 3,800 RPMs here with this car. It just ate itself up."

Teams typically turn their engines between 8,500 and 9,500 RPM at Richmond, depending on gearing.