Penske Racing has been hard hit by penalties for a technical infringement at last weekend's Sprint Cup race at Texas Motor Speedway.

Both the #2 car of reigning Cup champion Brad Keselowski and the #22 of his team mate Joey Logano failed pre-race inspection and were required to change rear-end components on the car. The delays caused Logano to be late lining up for the race and forced him to start from the back of the grid, although he still fought back to finish in fifth place by the end of the NRA 500.

On Wednesday, NASCAR announced that both cars had been found to be in breach of Sections 12-1, 12-4J and 20-12 of the Cup series rulebook, which includes fitting new suspension components to cars without having previously submitted them for approval to NASCAR scrutineers, and which must not allow in-race movement or realignment of the parts beyond normal usage tolerances.

As a result of NASCAR's findings, Keselowski and Logano both lose 25 Cup championship points which in Keselowski's case will drop him from second to fifth place in the standings, while Logano will fall from ninth to 14th. The #2 and #22 also lose the same number of car owner points apiece for Roger Penske.

More seriously for the teams, the two crew chiefs involved - Paul Wolfe and Todd Gordon - have been suspended from competition for the next six Cup races and the non-championship Sprint All-Star exhibition event. Keselowski had spoken out on Monday about his fears that Wolfe faced a lengthy suspension, and that he feared for his 2013 championship hopes without him.

Both Wolfe and Gordon have additionally been fined $100,000. The car chiefs, team engineers and team managers for both the #2 and #22 were also all handed six race suspensions but escaped fines. All those involved have additionally been put on NASCAR suspension until the end of 2013.

However Keselowski himself has escaped being penalised further for his outspoken comments against officiating at last weekend's event (see separate story.)

"No, we're not," said NASCAR Chairman and CEO Brian France on Monday when asked whether Keselowski faced sanctions for his blistering remarks. "That's the beauty of NASCAR, we do allow the drivers to express themselves in that way, even if they say things that we would disagree with. And I would certainly disagree with everything that he said."

There have been rumours circulating around the paddock that NASCAR took a closer-than-usual look at the two Penske cars at Texas after being 'tipped off' to something unusual by one of the team's competitors, as-yet unconfirmed and not identified. Hendrick Motorsports' Jimmie Johnson was parked next to Keselowski in the garage at Texas while Logano had another Hendrick driver, Jeff Gordon, as his own neighbour for the weekend.

Penske Racing said in a terse statement that they would exercise their right to appeal the penalty notices: "Penske Racing received communication today from NASCAR regarding penalties they have issued against the #2 and #22 teams. Penske Racing will appeal utilizing the appropriate NASCAR process. We have no further comment at this time."

Meanwhile, Martin Truex Jr. has also been penalised after it was found in post-race technical inspection that the #56 Michael Waltrip Racing car was running under the minimum front ride height.

Truex loses six Cup championship points (with an equivalent deduction in car owner points) which will drop him from 16th to 19th position, and crew chief Chad Johnston has been fined $25,000 and placed on NASCAR probation until June 5, but has not been suspended.

"Michael Waltrip Racing is sensitive to working within the guidelines of NASCAR policy," the team said in a press statement released soon after the penalties were announced. "This infraction clearly occurred as a result of a malfunction caused by race conditions. Therefore, we will not appeal. We thank NASCAR for providing a fair and equitable platform for all of its competitors and respect its decisions."

Away from Texas, NASCAR also took a dim view of Ron Hornaday Jr.'s driving at the end of the Camping World Truck Series race at Rockingham Speedway, when he retaliated under yellow against Darrell Wallace Jr. for perceived blocking. Hornaday was send to the back of the grid for wrecking the other truck, and has now been cited for violating section 12-1 of NASCAR's rulebook (actions detrimental to stock car racing - altercation with another competitor on the race track during a caution period.)

Hornaday Jr., who this season is driving for NTS Motorsports, has been handed a $25,000 fine and docked 25 Truck Series points, which drops him down from fourth place in the standings to 13th. He will be on NASCAR probation until June 12. Hornaday has not yet indicated whether he intends to exercise his right of appeal over the judgement.

Normally penalty notices from a race weekend are handed out on Monday or Tuesday, but this week's announcements were delayed until after Keselowski, Wolfe and Penske attended a reception in their honour at the White House hosted by the President of the United States, Barack Obama on Tuesday.

The event went ahead this week despite the bomb explosions that ripped through the end of the Boston Marathon on Monday, which will inevitably result in the tightening up of security at all sports events next week including NASCAR's Kansas races and the IZOD IndyCar Series race at Long Beach on Sunday.

"We've had this scheduled for some time, and events have a way of intervening," said President Obama before a crowd that included NASCAR chairman Brian France. "Obviously, our minds right now are with our fellow Americans and the fans that came from all over the world that went yesterday to run and cheer on another great American sporting event, the Boston Marathon.

"I know the entire NASCAR family shares with me a great sense of loss for the victims, and we pray for their loved ones," he added, calling the motor racing series a great American sport. "We're going to uncover whoever was responsible for yesterday's cowardly act, find out why they did it, and they will be brought to justice. But one of the things I firmly believe in is that America is strong, and we are resilient, and we don't let such cowardly acts get in the way of our lives."

"I think he had a great message about the solidarity that sports create," Keselowski said afterwards. "When you look at a sporting event, you see a nation as one. I think that kind of ties in, especially after a tragedy, how people come together.

"I think that makes us all realize how common our interests really are, when it seems sometimes they're not," he added.