NASCAR Narrows Ford Taurus Spoilers
NASCAR may be on the right track with its latest aerodynamic rule change.
The stock car sanctioning body, hoping to even out the competition in its premier Winston Cup series, has made its second modification this month to the rear spoiler of the new Ford Tauruses.
The latest change, coming after extensive wind tunnel testing last week at Lockheed Aviation in Marietta, Ga., leaves the height of the Taurus rear spoiler intact at 4 3/4 inches, but cuts the width by two inches to 55.
Terry Laise, chassis and body development engineer for General Motors, said, ``It’s a step in the right direction. ... I’d say it goes at least 80 percent of the way toward correcting that difference. ... I think we’re ever so slightly behind the Ford as far as absolute downforce performance, but close enough that we should be able to be competitive.″
All other spoiler and front air dam measurements on the Fords, the Chevrolet Monte Carlos and Pontiac Grand Prixs remain the same heading into the TranSouth Financial 400 on Sunday at Darlington Raceway.
``After going to the wind tunnel and looking at our findings, we found the downforce on the three makes was not that dramatically different,″ NASCAR spokesman Jeff Motley said Tuesday.
``Taking two inches off the width of the Taurus rear spoiler will have more effect on the drag of the car than on the downforce. That’s where the wind tunnel showed us that the Chevrolets and Pontiacs needed help the most.″
Air flowing over the top of the car hits the spoiler _ a piece of sheet metal rising from the rear deck of the car, and causes downforce, or downward pressure on the car. That helps it stay solidly on the track through the turns.
Drag comes from the air flow around the sides of the car and also helps pin it to the track as it hits the ends of the spoiler. The latest change will take the ends of the Ford spoiler almost completely out of the air flow.
The new Tauruses, developed in the past year as a replacement for the discontinued Thunderbirds, have had an apparent edge in aerodynamics through the first four races of the season.
After fairly even performances in the first two races, with General Motors victories in both, Ford took the first seven spots and 13 of the top 14 at Las Vegas. NASCAR quickly took a quarter-inch off the rear spoiler height of the Tauruses before the Atlanta race.
A Pontiac won at Atlanta, but eight Fords followed it across the finish line.
At that point, NASCAR impounded two of each model to take to the wind tunnel.
By taking away some drag from the Fords, NASCAR hopes to slow them down just enough to make things more competitive.
Motley called the most recent change ``minor compared to the first change we made.″
Paul Andrews, crew chief on the Ford that Jeremy Mayfield has driven to second place in the season standings, said the change does affect downforce as well as drag.
``The fact that the rule change takes more rear downforce away isn’t as big a concern as the fact that it changes the characteristics of the downforce,″ Andrews explained. ``From a pure downforce standpoint, this isn’t a tremendous change. But it is significant.″
The Tauruses lost 14 1/2 square inches of rear spoiler with the first rule change and another 9 1/2 inches with this one. They started the season with 285 square inches, and now we have 261.25, so they’ve lost almost 10 percent of what they had to start the season.
``Make a change of 10 percent anywhere else in the car and it’s a major, major impact,″ Andrews added. ``Ten percent here is a pretty big impact. It’s not that it can’t be dealt with, but some more time would be really nice.″