NASCAR officials are satisfied heading into next month's Speedweeks despite Preseason Thunder's top speeds that were faster than those registered at December's Goodyear tire test at Daytona International Speedway. There was as much as a 14 mph differential between qualifying and drafting speeds during three days of testing.

One morning session was rained out, which left one morning exclusively devoted to single-car runs and then four sessions in which drafting was allowed. However, single-car and two-car runs still dominated, with no drafts of more than six cars seen.

NASCAR managing director of competition John Darby said he expected nearly a 5 mph difference between two-car and mass-pack drafts, and he expressed no concern.

NASCAR went from a 30/32nds-inch plate at the tire test to a 29/32nds-inch plate for January. At the time of the change, NASCAR officials said they were anticipating teams would make gains and the desire was to keep them within a reasonable limit.

Darby said that limit wasn't reached at testing.

"We're a little bit slow, yet, but when you get 50 real race cars with real race engines and everything, I'm sure they'll pick [speeds] up a little bit more," Darby said, adding that he didn't anticipate another plate change. "Right now everything looks to be fine. Like I said, the speeds are probably on the conservative side, but when they bring back the real product I expect that to change a little bit."

Darby agreed a more stringent technical inspection that's in place during an actual event would also come into play.

Teams seemed to avoid mass drafts because they didn't want to risk their labor-intensive superspeedway race cars. But what teams found out while exploring two-car drafts was how effective they were.

The Penske Racing duo of 2004 Cup champion Kurt Busch and 2010 Nationwide Series champ Brad Keselowski ran dozens of laps in tandem Saturday and ended up atop the speed chart, with Keselowski's best lap of 198.605 mph.

"If you look at two cars hooked up, you've got half the [aerodynamic] drag and twice the horsepower -- that's how that works, in its basic terms, not scientifically," Darby said. "If the two-car speeds are where they're at, you could probably estimate [large pack] drafting speeds at 193-194, somewhere around there."

Darby stated the obvious.

"It's still drafting," Darby said. "Ultimately that's still what they're doing but the drivers have found a way to maximize it now."

Speed in testing isn't always a barometer for success at Speedweeks, and while acknowledging that, Keselowski was certainly pleased before he left Daytona Saturday evening.

"We're all racers, we want to win everything we do," Keselowski said, grinning. "But the important thing, when you're fast in a session like that is to not give anything up for when you come back and to be smart, and be fast when it counts. Right now don't count, but it sure is a lot of fun."

Keselowski refused to disclose any specifics of what he and his teammate learned running together, taking turns leading and following, but he knew one thing.

"The race is going to be crazier than ever," Keselowski said. "It's a completely new breed of racing and it's going to take an intelligent duo to pull it off at the end."

Keselowski likened coordinating the two-car draft to running a sprint relay race in track and field.

"From a driver's side, it's similar to a baton relay," Keselowski said. "If you have the two fastest runners in the world and you put them in a baton relay and they can't exchange [the baton], an average Joe Schmoe that can exchange will beat 'em, so it's just being smart."

His teammate used a different analogy to draw the same conclusion.

"I think it's more the two drivers working together to make it go fast," Busch said. "There are different combinations of tape on the grill and you have to be good on your exchange when you're going back and forth on who's gonna push and who's gonna lead -- so it's almost like you're gonna have to learn how to dance with everybody out there to make it work, if you want to be up front."

And while he said he initially was frustrated at not being able to get enough cars on track to try a mass draft, Keselowski revealed a revelation in the end.

"As the weekend progressed it became more and more obvious that the thought of having a big pack -- we might be seeing the extinction of that here," Keselowski said. "It won't be at the front -- how about that?"

Keselowski cited an episode right after the Saturday lunch break, in which six cars immediately hooked together, with Keselowski and Busch a good distance behind them. In less than two laps, the six cars broke into three pairs, but the Penske pair never appreciably caught up, even though they never stopped working together.

"Like I said, I think we're slowly starting to see the extinction of the big pack," Keselowski said. "For good or for bad I don't know -- I think it's probably for good because the runs, the racing and the passing is better than ever."

"It's definitely interesting the way it's playing out, because we didn't see a whole lot of big [pack] drafting, just a lot of two-car stuff," Keselowski's crew chief Paul Wolfe said. "It'll be interesting how that all plays out when we get more cars out there. The speeds were up there pretty good with that two-car breakaway but it seems like in the bigger packs it's actually slower -- which isn't what you would think. It doesn't seem right, but that's kind of what we're seeing"

Darby seemed to dispute the disappearance of pack racing, but not the race's ultimate deciding factor.

"It's a neat tool," Darby said of the tandem drafts. "As you watch the race, it's not something that you'll see [regularly]. I doubt we'll see pairs of cars from green flag to checkered flag, but as the race winds down to that final 20 miles it'll be time to find your partner and see who you're going to work with to get to the front."

"It's hard to know how important the big, big draft is going to be," Busch said. "But when you get down to the end you've got to have that two-car draft scienced out. When we were doing the tire test in December, cars were forced to stay in big packs, to wear out the tires and stay together for 25 laps.

"Now we're here on our own, with no rules and NASCAR hasn't stepped in about the bump-drafting -- and two cars are going to be faster than any other combination out there."

What drafting happened did disclose a couple things about the markings on the newly-paved race track. Darby said NASCAR officials saw no need to change anything, despite some reservations by Kevin Harvick, in particular, about the placement of the double-yellow lines marking the lower boundary of the race track.

"The hardest thing for me is the lines. The yellow line at Talladega is actually painted, I believe, on the race track and the one here is off the race track, on the apron," Harvick said. "So [Thursday] I touched the apron and about wrecked, so I think that that's going to be the biggest deal, is just keeping your car off the apron."

Darby said NASCAR considered doing away with the double-yellow "out of bounds" line, but "it took longer for you to ask me the question than what it took to make the decision to leave it there."

The only on-track change between now and Speedweeks, Darby said, would be painting the lane lines.

"We have had some conversations with a few of the drivers, how that's helpful to them, especially when they're in a draft and three-wide," Darby said. "It just gives them some sort of a guide, to understand how much room they've got, above and below them.

"Talking to the speedway [officials, Saturday] morning they said they would probably paint those right before the stock cars start in February."