NASCAR has introduced technical changes to the cooling system on Sprint Cup Series cars in the hope of limiting the two-car tandems that prevailed during Saturday's Budweiser Shootout at Daytona.
Effective for Thursday's Gatorade Duels, which will complete the starting order for the Daytona 500, the dimensions of the front grille opening on the cars will be reduced to a maximum of 50 square inches and also a pressure-relief valve set at 33psi will be fitted to radiators.
The move will drastically reduce engine cooling, hoping drivers will have to look for "clean air" much more than they did during Saturday's event, thus reducing the number of laps a car can push another one before water temperatures peak on their gauges.
During the non-points Bud Shootout, the usual big packs of cars traditional of restrictor plate racing were replaced by a new style of running in pairs, which proved to be the most effective way of gaining speed and thus getting to the front of the field.
The new smoother surface at Daytona allowed for the technique to develop, as the bumpy old asphalt prevented bump-drafting in the turns in the past. This, coupled with the low ambient temperatures from Saturday, created perfect conditions for cars to push for long stretches, Jamie McMurray actually bumping winner Kurt Busch for 14 consecutive green-flag laps.
"As an engine builder, this is a big change for a big race, so we're gonna do a lot of homework today and tomorrow and, hopefully, be prepared when we go back there on Wednesday and Thursday," said Ford engine builder Doug Yates. "If we need to do some more research before the 500, then we will."
The changes are also safety-oriented, officials aiming to bring speeds down as averages broke into the 206mph while running in the draft on Saturday's race.
"We can all agree from the competitors and NASCAR that 206 is probably a little bit to the extreme side," said Cup series director John Darby.
Teams will be able to sample the new cooling parameters during practice next Wednesday. However, further changes could be introduced like reducing the size of the restrictor plate, which remains at 29/32nds of a inch, the same used during testing last January.
"I wouldn't be surprised from the speeds that I've seen that we could have a plate change, so we are preparing as if that might come," Yates added.