ALTON, Va. -

It's race time in Martinsville. The STP 500 is Sunday, but before fans around the world watch the big race and even before the race cars arrived, tires had to be tested for the track.

The National Tire Research Center in Halifax County tests Goodyear tires, the official tire of NASCAR. They're being used at Martinsville Speedway this week.

The research helps the company chose what tire is right for each track and has put the area on a global map.

"It doesn't really look as big as it really is. But it's actually 14 feet tall and the base as 12 foot by 12 foot," said Kevin Kefauver, the technical director of the tire research center, describing the machine used to test the tires.

The strange contraption is helping keep tire companies around the world build better products.

"It's real important in performance in rain, snow, cornering, straight ahead, breaking, acceleration, energy loss," said Frank Della Pia, the executive director of the tire research center.

Companies fly in to Alton, Virginia to understand how tire construction impacts cars at speeds up to 200 miles per hour without leaving the lab.

"It's created a spring board for us to create all kinda of other offerings and create all kinds of other job opportunities," Della Pia said.

One huge arm holds the tire and can put different pressures on it, mimicking not only the highway but the forces and loads from any race track, and at Martinsville Speedway.

"All of the teams that get that data will use that data however they see fit to make their race cars faster," Kefauver said.

Goodyear uses the research from the center to pick specific tires for each track. Drives use different tires at Martinsville Speedway than they do at Daytona International Speedway.

The Tire Research Center is part of Virginia Tech and is booked through this year for testing.

That demand allowed the company to hire more employees, growing from 25 workers to 30 by this summer.