With the Nextel Cup paddock buzzing following the news that the cars of Jeff Gordon and Jimmie Johnson had failed technical inspection and would not take any part in Friday's on-track proceedings at the Infineon Raceway Bobby Labonte set fastest time in opening practice.

Discovering what the new Cars of Tomorrow felt like on the 1.99-mile Californian road course for the first time Labonte led the way in the #43 Petty Enterprises Dodge with a time of 77.539secs after a session filled with minor spins and 'offs.'

Robby Gordon and Kurt Busch were second and third fastest with Tony Stewart, one of more than half a dozen drivers to overstep the limits of the new cars and run off-track, in fourth place on the timesheets.

Ron Fellows was the best placed of the 'road warriors' in sixth position for Hall of Fame Racing while Juan Montoya was 13th in his Chip Ganassi Racing Dodge. Further down the list Boris Said was 25th after a spin, the returning Terry Labonte 33rd for Michael Waltrip's #55 Toyota team and Belgian native Marc Goossens 40th for the debuting Riley-D'Hondt Motorsports team.

Gordon and Johnson could do little but what the on-track action from the sidelines as their respective crews worked on making the front of their cars conform to NASCAR's templates and will be faced with starting their set-up work from scratch on Saturday morning.