Bobby Allison's uncanny knack for evading trouble paid off again today as he steered safely through a grinding 20-car crash on the fourth lap, then easily outdistanced the remnants of the once-powerful field in the $280,000 Winston 500 Grand National stock car race.

A crowd of 100,000 saw Allison take over the lead with about 100 miles left when Neil Bonnett, who had led most of the race until then, parked suddenly with a broken engine. That left Allison an insurmountable lead, and he finished more than a lap ahead of pole division starter Darrell Waltrip, and two laps ahead of Buddy Arrington.

Only one driver, Cale Yarborough, required hospitalization after the wreck, which occured a lap after the leaders had been clocked at better than 203 miles per hour on Alabama International Motor Speedway's 2.66 mile trioval.

Yarborough already climbed uninjured out of his car after the pileup when another car that was still spinning pinned him between two cars. His crew chief Junior Johnson said, however, "Cale's all right. He just jammed his foot between the two cars. He'll be driving again next weekend."

The wreck developed at the start-finish line, which is at the entrance to turn one, as Buddy Baker tried to pass Bonnett on the outside for the lead. Baker's car suddenly broke loose - the consensus was a tire went flat - and veered into the wall. Yarborough and Benny Parsons, following closely, slammed into Baker and cars behind them went everywhere to try to avoid the wreck.

Before the billowing dust and exploding debris settled, a dozen of the top contenders' cars had been battered beyond repair, including those of Baker, Yarborough, Parsons, Tighe, Scott, Lennie Pond, Dale Earnhardt and Dick Brooks.

Most of the rest involved, Richard Petty, Waltrip and Donnie Allison among them were able to continue, but hard-pressed to challenge for the lead.