The 18-wheeler hauling two race cars and enough parts and tools to fix any unforeseen or anticipated accident departed Furniture Row Racing’s Denver headquarters Wednesday, making Thursday a behind-the-scenes workday for the meat-and-potatoes crew building for next week and beyond.

Shop foreman Johnny Roten and his North Carolina accent were in charge at the 35,000-square-foot facility, demanding accountability for what happens to driver Martin Truex Jr. and the No. 78 Chevrolet in the NASCAR Sprint Cup race Saturday at Kansas Speedway.

But while the excitement for Saturday is high — Truex is second in the standings with nine top-10 finishes in 10 races — the focus is on the ensuing races in Charlotte, N.C.; Dover, Del.; and Pocono, Pa.

What Truex drives Saturday will not be the car he will have in the coming weeks, but rather what is being built by Roten and his 35-member nonrace crew. There is no room for mistakes — an unscrewed bolt, an expired part — and no off days while the race-weekend crew is on the road.

WATCH: Behind the scenes at Furniture Row Racing

FRR has built 104 race cars in Denver since its 2005 big-league debut.

“The average Joe sitting there watching a race on TV with a beer in his hand, he’s thinking, man, they got a primary car and backup car and they run them every week,” said Roten, 49. “But the truth is, the car you seen last week, heck, it might not run for another six weeks. It’s a 15-car rotation with us, and we calculate mileage on every part.”

Roten’s crew builds each car for a specific track, based on superspeedways (2½ miles-plus, intermediates (1½ miles), short tracks (1 mile or less) and road courses. So even if Truex takes the checkered flag Saturday — FRR’s only win was Regan Smith in 2011 — they don’t deviate from the plan.

“It’s all about my guys and you have to have faith in your program, and (team owner) Barney (Visser) gives us everything we need to do the job right,” Roten said.

There’s nothing more Roten and the other nonrace weekend employees can do about Saturday, the 11th race of the season. They have given Truex, general manager Joe Garone, crew chief Cole Pearn and director of competition Pete Rondeau the best that they have.

Roten, who previously worked for North Carolina-based teams including Bill Elliott Racing and Evernham Motorsports, will watch Saturday’s race on his couch with his family.

“I’m a pretty high-strung guy,” he said. “It’s usually me, my wife and a couple of our kids on the couch. I used to have racing parties, but it’s really hard for me to focus on what’s going on. I’m just real intense and I want to have my radio on — I listen to everything the team says.”

Jason McLaren is FRR’s setup guy at the shop, and he too watches the races from his couch. The Arvada native, 33, is in charge of making sure a race car is built to NASCAR specifications. Truex previously said his cars have required very little fine-tuning from the first practice session to race day this year, his second with the team. In 2014, Truex finished 24th in the standings.

“It’s wonderful what we’re doing now, and great to see this team grow since I’ve been here,” said McLaren, who has been with FRR since the beginning. “It’s really enjoyable now. When you’re running bad, it’s still enjoyable but … there’s nothing like coming to the shop when you’re running well.”

Mike Chambers: mchambers@denverpost.com or twitter.com/mikechambers