Tech Q&A: Jimmy Fenning

February 6, 2001
11:19 AM EST (1619 GMT)

Q: On a red flag stop if the car does not restart do they assume their position or do they go to the rear of the field? -- Scott Brown, Pottstown

A: NASCAR allows cars to assume their position, even if the motor stalls.

Q: What exactly is the mechanical difference between a qualifying motor and a race motor? -- David Clark, Covington, Ind.

A: The qualifying motor has huge parts in there, and if you get it hot you don't have to worry about it. Now a race motor, you don't want to get it too hot.

Q: What does it mean when a tire is "equalized", and what causes it? -- Steve Mace, Bellflower, Calif.

A: That's where the inner liner and the outer tire have the same air pressure. That is caused by the inner having a rip or something where the air leaks out, that's what causes it to equalize.

Q: Does NASCAR regulate the PSI in the airguns that they change tires with? -- Jeff Bagley, Reading, Penn.

A: No, we do that ourselves. It varies depending on the tire changer. Some guys like more than others.

Q: What does the button on the steering wheel do that the drivers keep pushing during the race? -- Jim Bugh, Cherokee, Iowa

A: That's actually the driver's radio. He talks to the crew by pushing that button.