Five things to know about what's going on at Daytona International Speedway in advance of the season-opening Daytona 500 on Feb. 23: --- HENDRICK ENGINES: Tony Stewart, Danica Patrick and Bobby Labonte blew engines during pole practice for the Daytona 500 on Saturday, creating concern about Hendrick Motorsports power plants. Stewart and Patrick are teammates at Stewart-Haas Racing, and Labonte is driving for HScott Motorsports. Both teams lease engines from Hendrick, which also fields cars for six-time and defending Sprint Cup champion Jimmie Johnson, four-time champ Jeff Gordon, Dale Earnhardt Jr. and Kasey Kahne. More...