Chris Buescher (Roush Fenway Racing), Chase Elliott (Hendrick Motorsports) and Erik Jones (Joe Gibbs Racing) took part in NASCAR's low downforce test Tuesday at Michigan International Speedway as NASCAR and Goodyear officials began looking for an aerodynamic answer to the 2-mile track located in the Irish Hills region.
This year's August race at MIS, as well as the Sprint Cup race at Indianapolis Motor Speedway, featured a high drag configuration that failed to live up to officials' expectations. Aero changes in place for that package included a 9-inch spoiler (an increase of three inches) with a 1-inch wicker bill; a 2-inch leading edge on the splitter and 43-inch splitter extension panel (radiator pan); and a rear fascia extension panel similar to those used for superspeedway events.
The package appeared to increase the impact of the draft, but had little or no effect on allowing trailing cars to make passes.
For the MIS test on Tuesday, cars were outfitted with smaller splitters and radiator pans and a shorter three-and-a-half inch spoiler, much like the configuration used at Kentucky and Darlington this season.
"(It's) definitely different than the XFINITY car," Buescher said during a break in the test. "… If you asked Cup guys that were here earlier this year with the high drag package, drivability probably wasn't an issue. It was probably pretty easy to drive, whereas now it's a bit of a handful. We're lifting out of the throttle a little more than what data shows from earlier this year. …
"It's a big difference and I think the race is going to show a pretty big change as well."
While none of the three drivers at the test compete full-time in NASCAR's Sprint Cup Series, all three have experience in the cars. Buescher, the XFINITY Series points leader, had six Sprint Cup starts earlier this year in the Front Row Motorsports No. 34 Ford, and did extensive testing for Roush Fenway before private testing was banned after 2014.
Elliott, who will move from the XFINITY Series to Sprint Cup full-time next season when he takes over the ride being vacated by four-time Sprint Cup champion Jeff Gordon, made five starts this season in a fifth entry for Hendrick Motorsports to prepare him for 2016.
Jones, the Camping World Truck Series points leader, was pressed into service after JGR driver Kyle Busch was injured in a season-opening crash at Daytona. While the bulk of his additional duties came in the XFINITY Series, Jones does have one Sprint Cup start, at Kansas, filling in for Busch in the organization’s No. 18 Toyota.
Elliott ran the low downforce package at Darlington and said he hopes "this is a small step and it continues down this path.
"I don't think it needs to stop here with this low downforce package," he said. "I think it needs to continue if that's the direction that we need to go in and not get satisfied too soon."
All three drivers said there seemed to be more off-throttle time with the new package in part due to the faster lap times -- Elliott said he wasn't sure of the top speeds but guessed they were somewhere in the 210-mph range.
"A little bit more challenging to drive, more driver input which is nice," noted Jones, who was called upon as a replacement for JGR regular Denny Hamlin. "Overall for the Cup Series, I think this is probably a step in the right direction. I definitely think this is a pretty good change."
Jones said it made sense for him to take part in the test since he was already in the area -- he hails from Byron, Michigan.
"I'm sure Denny wants to get rested up and be at 100 percent for the Chase," he said. "For me, it's pretty cool deal to get in a Cup car and get that experience, feel out the new package. Anytime I can get laps in these cars is beneficial."
Hamlin is one of 12 drivers competing in this year's Chase for the NASCAR Sprint Cup.
Shorter Valve Stems
Some Sprint Cup Series teams began using shorter valve stems in their tires two weeks ago at Charlotte Motor Speedway, a move that they hope will lessen the likelihood of suffering a flat tire caused by contact with lug nuts.
There have been several instances of flat tires shortly after pit stops this year, and at least one crew chief has said lug nuts hitting the valve stems during tire changes have been the culprit.
The shorter stems, it is believed, are less likely to be struck in the rush of a pit stop.
"It's not a new design; we just shortened it as much as we can to allow the same core to be inside the valve stem," Greg Stucker, Director of Race Tire Sales for Goodyear, said. "It just gets it out of the way a little bit more.
"It's not going to be a fix; but that's all we can do right now. It's a reaction to the people wanting us to do something so we did it as quickly as we could."