Five of the 36 races on the 2007 NASCAR Nextel Cup schedule are impound races. Those events are both races at Richmond, both races at Talladega, and the July Daytona race. But what exactly is an impound race?
It's pretty simple. At an impound race, car setups are not allowed to be changed between the time race qualifying ends and the race begins. The cars are "impounded" by NASCAR during that time, with work allowed only under special circumstances and with the prior approval of NASCAR. Impound races usually feature two Friday practices and Saturday Bud Pole Qualifying instead of the traditional Friday Bud Pole Qualifying and two Saturday practices.
NASCAR officials said the idea of impounding the cars came about as a way to discourage teams from spending time and money researching setups that they will use only for qualifying. It was first implemented in 2005, with 21 of 36 races run under the rule. At the time, NASCAR Nextel Cup Series director John Darby said it was his hope that the rule would be good for competition.
"Ultimately, all the teams will arrive at the track with a focus on one goal," Darby said. "That goal will be to have the best possible race setup, and hopefully that will enhance the overall competitive element throughout the field."
However, after criticism in the garage that the schedule changes caused confusion and wasted time for teams, NASCAR relented and the impound race schedule was dramatically reduced to five in 2006.
"In the overall scheme of things, it didn't fit the way we thought it would," said NASCAR president Mike Helton in announcing the change. "We just wanted to back off that and take a look at it from a different angle. We just haven't found the right balance yet."
Here is how the impound rules are stated in NASCAR's rulebook:
Following qualifying for the NASCAR Nextel Cup Series event, the cars will be escorted to their respective garage stalls by a NASCAR official (with the exception of the top five cars, which will be placed in a designated area for post-qualifying inspection).
Once the car is pushed to the garage stall, only two crew members will be allowed to remain in the garage.
The following work list will be allowed:
1. Shut off electrical switches and master power switch
2. Remove radio
3. Check air pressure in tires
4. Cover the car
5. Crewmembers exit garage and garage doors close
Pit road selection will be immediately after the last car has qualified.
Procedure for race day for NASCAR Nextel Cup Series teams:
Garage Stall: A maximum of two crew members per car, accompanied by a NASCAR official, will be allowed in the garage stall. Below are the procedures that will be completed in the garage stall:
1. Plug in oil heater (if teams use a generator, it must remain outside the garage)
2. Open hood
3. Prime oil system
4. Back car out of garage to start
5. Turn master switch on
6. Open oil cooler bypass valve (optional)
7. Start engine
8. Close hood
9. Set tire pressure
10. Torque wheels
11. Install radio and water bottle
12. Remove or repair tape on front of car (i.e. grille, valance, brake ducts.)
13. If applicable, BST or Pi Research may replace equipment batteries under NASCAR supervision.
Teams may not:
1. Enter the garage without a NASCAR official present
2. Jack up any part of the car
3. Add water or pressurize the cooling system
4. Climb inside the car
5. Adjust wedge bolts, shocks or sway bars
6. Add fuel, oil or brake fluid
7. Remove air box
8. Adjust fenders, spoiler or any body components.
Fuel pumps: A maximum of three crewmembers per car at any time, escorted by NASCAR officials, may go to the fuel pumps. For tracks 1 mile and under, a maximum of two gallons of fuel will be added. For tracks 1½ miles, a maximum of three gallons of fuel will be added. For tracks above 1½ miles, a maximum of four gallons of fuel will be added.
Height platform: A maximum of three crewmembers per car at any time, accompanied by NASCAR officials, may escort the respective car to the height platform.
1. Adjust front and rear wedge bolts: A maximum of one turn for front bolts. A maximum of 1½ turns for rear bolts.
2. Adjust track bar at frame end adjuster. No maximum on track bar adjustment.
3. Adjust external shock bleeds.
Teams may not:
1. Change any components.
2. Add spring inserts.
Scales: A maximum of three crewmembers per car at any time, accompanied by NASCAR officials, may escort the respective car to the scales. Any car that does not meet required weight specifications may be subject to penalty. After completion, the generator will be reconnected to the car and pushed to pit road. Generators will be permitted out on pit road with the car.