1990 Champion Spark Plug 400

The 1990 Champion Spark Plug 400 was the 19th stock car race of the 1990 NASCAR Winston Cup Series season and the 21st iteration of the event. The race was held on Sunday, August 19, 1990, before an audience of 60,000 in Brooklyn, Michigan, at Michigan International Speedway, a two-mile (3.2 km) moderate-banked D-shaped speedway. The race took the scheduled 200 laps to complete. At race's end, Roush Racing driver Mark Martin would manage to dominate the late stages of the race to take his third career NASCAR Winston Cup Series victory and his second victory of the season. To fill out the top three, Hendrick Motorsports driver Greg Sacks and Blue Max Racing driver Rusty Wallace would finish second and third, respectively.

Background
The race was held at Michigan International Speedway, a two-mile (3.2 km) moderate-banked D-shaped speedway located in Brooklyn, Michigan. The track is used primarily for NASCAR events. It is known as a "sister track" to Texas World Speedway as MIS's oval design was a direct basis of TWS, with moderate modifications to the banking in the corners, and was used as the basis of Auto Club Speedway. The track is owned by International Speedway Corporation. Michigan International Speedway is recognized as one of motorsports' premier facilities because of its wide racing surface and high banking (by open-wheel standards; the 18-degree banking is modest by stock car standards).

Entry list

 * (R) denotes rookie driver.

Qualifying
Qualifying was split into two rounds. The first round was held on Saturday, August 18, at 11:00 AM EST. Each driver would have one lap to set a time. During the first round, the top 20 drivers in the round would be guaranteed a starting spot in the race. If a driver was not able to guarantee a spot in the first round, they had the option to scrub their time from the first round and try and run a faster lap time in a second round qualifying run, held on Saturday, August 18, at 1:30 PM EST. As with the first round, each driver would have one lap to set a time. For this specific race, positions 21-40 would be decided on time, and depending on who needed it, a select amount of positions were given to cars who had not otherwise qualified but were high enough in owner's points; up to two were given.

Alan Kulwicki, driving for his own AK Racing team, would win the pole, setting a time of 41.147 and an average speed of 174.982 mph in the first round.

Two drivers would fail to qualify.

Standings after the race

 * Drivers' Championship standings
 * Note: Only the first 10 positions are included for the driver standings.