Mudflaps or Canards: The NHRA Aero Experiment Everyone is Watching

Yahoo

29-03-2025

When a drag racer talks about 'mudflaps,' don't envision the big, wide rubber strips with the slinky silhouettes behind the tires on semi haulers that keep mud, rocks, and debris from pocking car windshields on the Interstate highways.
What they're referring to is the canards, or 'air deflectors,' in front of the giant rear Goodyear slicks on an NHRA Top Fuel dragster.
They're the hottest tech topic on the NHRA Mission Foods Drag Racing Series; these additions are designed not for the advertising billboards they have become but for decreasing downforce, and reducing rear-wheel loads, all without causing a significant impact on other areas of the race car.
The NHRA is studying it all and has allowed crew chiefs to experiment with the panels for the next four races. The experiment started with last weekend's Arizona Nationals at Firebird Motorsports Park in the Phoenix suburb of Chandler.
Until the end of April, 'mudflaps' on Top Fuel dragsters will be optional. After the Arizona Nationals, the flaps are allowed at this weekend's Winternationals at Pomona, Calif., and the two four-wide events, at Charlotte and Las Vegas – and the NHRA Technical Department will be evaluating their effectiveness.
The Tech Department will reassess the mud flap after the trial period, working with Top Fuel teams to gather as much information as possible. If a team does not use mud flaps, the side of the Top Fuel body must be covered with a replacement body panel, with no bare chassis exposed.
Brian Corradi, current champion Antron Brown's crew chief, said, 'We don't need to have any tires failing. And they think that maybe you could take some downforce off the car by taking the mudflaps off, because we have nowhere else to go on the wing unless we change the wing design. So that's the plan.'
Brittany Force was one of the first to make a pass without the familiar flaps, at last week's Arizona Nationals, at Phoenix, and she clocked a 3.768-second, 329.10-mph performance. But that was right in her wheelhouse. Neither she nor Dave Grubnic, her crew chief, put their stock in either of the car's configurations.
Grubnic said, 'One run doesn't prove anything. We've been given the opportunity to explore [whether to use the mudflaps]. We've got to look at driveshafts. We've got to look at a lot of things. The car pretty much ran its number. It doesn't suggest the mudflaps did anything. It's way too early. Let's see what happens.'
Force's co-crew chief, John Collins, joined the debate about what to call them – mudflaps? Canards? – and his suggestion was to 'call them useless.'
Force has made runs both with and without mudflaps, and she said, 'There is a lot of theories and speculation around it. We're going to take all these four races to see what we could do, if it affects me as a driver, what it does to our car performance-wise. I'm excited to see.'
Public-address announcer Jason Galvin said Saturday, 'The one thing that we do know, just from talking to our friends at Goodyear last weekend, when these race teams took those air deflectors off the car, they were seeing significantly cooler temperatures on the tires on the top end compared to the cars that were still running them.'
Conditions were hot at Phoenix and are cool at Pomona, providing a wide array of data.
Drag-racing legend Don 'The Snake' Prudhomme ushered in the mudflaps in 1990, with technical expertise of General Motors/Pontiac engineers, in an effort actually to increase downforce on the dragsters – the opposite of what the purpose of them is today.
'One of the engineers put aluminum flaps out on the side of the car, and that changed everything,' he said. That gave us downforce and everything we needed. And that's how they got born. Now they're [made of] carbon fiber.'