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Major changes being made to cooling systems

December 15, 2011, Mark Aumann, NASCAR.com

Changes to cooling systems NASCAR's response to regulate tandem drafting

NASCAR has issued a new technical bulletin to its Sprint Cup teams, detailing major changes to cooling systems for 2012 Speedweeks at Daytona International Speedway in an effort to better regulate tandem drafting.

According to Chris Paulson, president and owner of C&R Racing Inc. -- which manufactures nearly all of the radiators used in NASCAR's premier series -- the sanctioning body will be significantly reducing the size of the radiators and changing the location of the grille openings before the cars return for Daytona testing in January.

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"[Sprint Cup Series director] John Darby is implementing a two-gallon maximum radiator size," Paulson said. "So in other words, the big, huge five-gallon radiators everybody's running will be down to two. And that accumulator can was a one-gallon max volume. It's going down to a half-gallon-sized can."

The idea is to make the cooling systems less efficient, Paulson said, forcing the cars to run in open air to keep water temperatures down.

"We'll probably see some result from that, but it's not going to be huge, mainly because they've got these things figured out now," Paulson said. "But it's still going to have an effect.

"The bigger effect is going to be moving the grille opening up to the bumper fascia area. Because now when they're tucked up behind another car, they're really going to kill all the air. So I think they're on the right track with that. They'll get the result that way."

In addition, NASCAR will require softer springs, a smaller rear spoiler and a baseline restrictor-plate size of 29/32ths of an inch, or 1/64th of an inch larger than the plate used for the 2011 Daytona 500.

"We had some productive tests at Talladega and Daytona in October and November and this rules package is a result of the information we were able to gather from those tests," Darby said. "Our goal was to put together a good, solid baseline aerodynamic package for the Preseason Thunder test at Daytona and we believe we've made a lot of progress in doing that.

"We want to be able to give the teams more options when it comes to drafting and we want to be able to reduce the difference in the speeds between the tandem style of racing and more of the pack style of racing that the fans are accustomed to seeing. We believe we're headed in the right direction with that."

Pressurized cooling systems had been used for years in open-wheel racing but made their way to NASCAR only in the past 12 years, Paulson said. And it wasn't until just a few years ago that teams realized they could run water temperatures well past the boiling point for entire races without appreciable damage to their engines.

That issue came to the forefront during last year's Budweiser Shootout, when drivers used tandem drafting throughout the entire race for the first time.

"I got called into the trailer the Sunday morning after the Shootout and although [NASCAR officials] weren't mad at me, they knew this was an evolution in cooling," Paulson said. "They just wanted to try to do something to fix it.

"NASCAR asked me personally if we could have manufactured 50 33-pound pressure relief valves by Wednesday -- before the Twins [Gatorade Duel qualifying races]. So we did just that. We built them at our shop at Indianapolis, shipped them to Daytona and put them together. And that's how the race was run."

The pressure was reduced to 25 pounds at Talladega, but had only a limited effect on tandem drafting. Paulson believes the new rules -- combined with changes to the restrictor plates and spoilers -- should have the desired effect at Daytona. But it won't eliminate tandem drafting entirely.

"It'll be a short number of laps, and they'll be peeking out a lot more," Paulson said. "They certainly won't be able to do a sustained lap-after-lap run. I think that'll be taken care of. But you'll see, for one or two laps, them hook up if they want to go and pass people.

"I think that'll mix it up a lot more. And it needs to. I don't disagree with NASCAR of their wish to break that up. It's really changed that type of racing."