Johnson a rose in midst of spoiler unknown at Texas

You just know you've got your world by the throat when you can waltz into a venue that just drips with uncertainty wearing a should-be-trademarked smile that chills seepage to iceberg consistency.

Four-time defending Cup Series champion Jimmie Johnson knows this weekend's events at Texas Motor Speedway leading up to Sunday's Samsung Mobile 500 is somewhat nebulous.

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Jimmie Johnson weighs in as Marc Fein and Marty Snider discuss what affect the spoiler may have at 1.5-mile Texas.

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So what, he says? For one thing, he's leading the championship -- something he's done four times in a row after the finale at Homestead -- but an area he rarely visits, or worries too much about, at this time of the season.

But this weekend is the third since NASCAR walked away from wings on its new car, after an aborted three-plus year experiment, and went back to spoilers.

In a lot of ways, it's probable that the transition was perfect -- from tiny Martinsville, where straight-ahead aerodynamic effect is negligible; to Phoenix, where it ratchets up quite a bit; to hairy Texas, one of the circuit's fastest tracks where aerodynamics play on these cars from every angle.

"When we were at Charlotte [testing in March], I wanted the first day to think that we noticed the side-force changes and the numbers from downforce and side force," Johnson said. "NASCAR has made adjustments to compensate for that and they wanted to overshoot that and give us a little more downforce and more side force. I think the location of the end plate on the wing was up in the raw air than the extension that's on the quarter panel. That was my opinion in the car the first day.

"As it wore on, I don't know if I just got used to the car and started adjusting to the car and then the track seemed to rubber up and change and become more familiar and kind of ended up with the same sensation that I have at Charlotte all the time. Then we roll into Martinsville and you can't notice anything there.

"Go to Phoenix and things seem to be as they were before at Phoenix. I'm going into Texas really forgetting about the spoiler. We talked about it, but when I get in the car and strap in, I don't have anything in my mind saying, 'OK, you have the spoiler so you need to think about this or drive the car differently.' It's been a smooth enough transition so far just to roll on out, hit the track and get to work." (Continued)