Michigan speeds reduced with left-side tire change

Officials from NASCAR and Goodyear seemed pleased with their decision to change the left-side tires on the cars for Sunday's 400-mile Sprint Cup Series race at the newly repaved Michigan International Speedway.

An additional Sprint Cup practice session was held on Saturday at Michigan. The 75-minute session was held immediately following the Nationwide Series race here, which was won by Joey Logano.

After several teams experienced tire blistering during Thursday and Friday's practice sessions at Michigan, NASCAR and Goodyear made the decision to use a tougher left-side tire for this race.

During Friday's second practice, Greg Biffle posted the fastest lap at 204.708 mph. The higher than expected speeds at Michigan caused significantly higher left-side tire temperatures and therefore blistering.

Goodyear shipped in enough tires for teams to have 10 sets of them for the race, which is the original NASCAR set limit for this event. Teams will run their original allotment of right-side tires.

Speeds were considerably less during Saturday's practice compared to the past two days. Tire temperatures were lower as well, and there were no reports of blistering.

Biffle topped the speed charts in this session with a lap at 195.647 mph.

"From what we saw in this final practice this evening, we're very comfortable with (the tires)," said Greg Stucker, who is Goodyear's Director of Race Tires. "I think all of our observations are reinforcement that, from a tire perspective, it was the right call."

Stucker also noted that Mark Martin, who had a number of issues with his tires during Friday's practice sessions, made a 21-lap run in the final session and said the tires "looked beautiful."

NASCAR gave teams the extra practice time to get familiar with the new tire as well as make further adjustments to their race setups.

"We have to treat this like we haven't been here," NASCAR Vice President of Competition Robin Pemberton said prior to the start of practice. "It's a new tire for this track surface, and we need to give the teams enough time to practice on it."

The additional session had mixed reviews from drivers. Some were limited on their practice time due to engine concerns.

"Our engine guys don't like us to run over a certain amount of laps, so I'm at my limit and can't practice anymore," Earnhardt Jr. said after completing 26 laps. "I would like to practice more, but I can't. My car isn't as good as I want it to be, but I can't practice anymore. This ain't cool."

Earnhardt Jr.'s last Sprint Cup win came four years ago at Michigan (143 races ago).

Earlier in the day, Marcos Ambrose won the pole for this race after he easily shattered the track qualifying record here with a lap at 203.241 mph. Forty drivers in the qualifying session recorded a faster speed than the previous track record of 194.232 mph, set by Ryan Newman in 2005. Nineteen of them topped 200 mph.

"We were out there trying to save miles on the engine, so we never really busted off a good run," said Ambrose, who was 11th quickest in practice. "The tire is very different. It hasn't got much grip. You are loose in, shake in the middle and then on the gas spin yourself out.

"It feels unbalanced and a little bit wobbly, and you don't want to be wobbly at 200 mph. You want to feel like the car is underneath you. I think we did enough stuff during practice to get a feel for what we need. We will make some adjustments tonight and get ready for tomorrow."

Newman applauded NASCAR and Goodyear for the tire change.

"I think it was absolutely the right call," he said. "The tire temperatures are way down. It was a good call by Goodyear and NASCAR."