1991 Champion Spark Plug 400

The 1991 Champion Spark Plug 400 was the 19th stock car race of the 1991 NASCAR Winston Cup Series season and the 23rd iteration of the event. The race was held on Sunday, August 18, 1991, before an audience of 90,000 in Brooklyn, Michigan, at Michigan International Speedway, a two-mile moderate-banked D-shaped speedway. The race took the scheduled 200 laps to complete. In the final laps of the race, Wood Brothers Racing driver Dale Jarrett would mount a late-race charge against Robert Yates Racing driver Davey Allison, passing Allison in the final lap of the race and besting Allison by at the finish to take his first career NASCAR Winston Cup Series victory and his only victory of the season. To fill out the top three, Penske Racing South driver Rusty Wallace would finish third.

Background

The race was held at Michigan International Speedway, a two-mile 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.

Entry list

' denotes rookie driver.

#	Driver	Team	Make	Sponsor
1	Rick Mast	Precision Products Racing	Oldsmobile	Skoal
2	Rusty Wallace	Penske Racing South	Pontiac	Miller Genuine Draft
3	Dale Earnhardt	Richard Childress Racing	Chevrolet	GM Goodwrench Service Plus
4	Ernie Irvan	Morgan–McClure Motorsports	Chevrolet	Kodak
5	Ricky Rudd	Hendrick Motorsports	Chevrolet	Tide
6	Mark Martin	Roush Racing	Ford	Folgers
7	Alan Kulwicki	AK Racing	Ford	Hooters
8	Rick Wilson	Stavola Brothers Racing	Buick	Snickers
9	Bill Elliott	Melling Racing	Ford	Coors Light
10	Derrike Cope	Whitcomb Racing	Chevrolet	Purolator Filters
11	Geoff Bodine	Junior Johnson & Associates	Ford	Budweiser
12	Hut Stricklin	Bobby Allison Motorsports	Buick	Raybestos
14	Mike Chase	A. J. Foyt Racing	Oldsmobile	Copenhagen
15	Morgan Shepherd	Bud Moore Engineering	Ford	Motorcraft
17	Darrell Waltrip	Darrell Waltrip Motorsports	Chevrolet	Western Auto
19	Chad Little	Little Racing	Ford	Tyson Foods
20	Buddy Baker	Moroso Racing	Oldsmobile	Rob Moroso Memorial
21	Dale Jarrett	Wood Brothers Racing	Ford	Citgo
22	Sterling Marlin	Junior Johnson & Associates	Ford	Maxwell House
24	Dick Trickle	Team III Racing	Pontiac	Team III Racing
25	Ken Schrader	Hendrick Motorsports	Chevrolet	Kodiak
26	Brett Bodine	King Racing	Buick	Quaker State
28	Davey Allison	Robert Yates Racing	Ford	Texaco, Havoline
30	Michael Waltrip	Bahari Racing	Pontiac	Pennzoil
33	Harry Gant	Leo Jackson Motorsports	Oldsmobile	Skoal Bandit
36	H. B. Bailey	Bailey Racing	Pontiac	Almeda Auto Parts
42	Bobby Hillin Jr.	SABCO Racing	Pontiac	Mello Yello
43	Richard Petty	Petty Enterprises	Pontiac	STP
44	Bobby Labonte	Labonte Motorsports	Oldsmobile	Slim Jim
49	Stanley Smith '	BS&S Motorsports	Buick	Interstate Batteries
52	Jimmy Means	Jimmy Means Racing	Pontiac	Alka-Seltzer
55	Ted Musgrave '	U.S. Racing	Pontiac	Jasper Engines & Transmissions
66	Lake Speed	Cale Yarborough Motorsports	Pontiac	Phillips 66 TropArtic
68	Bobby Hamilton '	TriStar Motorsports	Oldsmobile	Country Time
71	Dave Marcis	Marcis Auto Racing	Chevrolet	Big Apple Market
75	Joe Ruttman	RahMoc Enterprises	Oldsmobile	Dinner Bell Foods
79	Donny Paul	Paul Racing	Oldsmobile	Paul Racing
89	Jim Sauter	Mueller Brothers Racing	Pontiac	Evinrude Outboard Motors
90	Wally Dallenbach Jr.	Donlavey Racing	Ford	Donlavey Racing
94	Terry Labonte	Hagan Racing	Oldsmobile	Sunoco
98	Jimmy Spencer	Travis Carter Enterprises	Chevrolet	Banquet Foods

Qualifying

Qualifying was split into two rounds. The first round was held on Friday, August 16, at 3:30 PM 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 17, at 11:00 AM 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. If needed, a past champion who did not qualify on either time or provisionals could use a champion's provisional, adding one more spot to the field.
Alan Kulwicki, driving for his own AK Racing team, would win the pole, setting a time of 41.515 and an average speed of in the first round.
Donny Paul was the only driver to fail to qualify.
Full qualifying results
Race results
Standings after the race
;Drivers' Championship standings
Note: Only the first 10 positions are included for the driver standings.