It is hard to consider Team Penske an underdog at the Indianapolis Motor Speedway. In their thirteenth year of participating in the Indianapolis 500, they had won four times and finished second four times. Still, 1987 was a year that Al Unser, Sr. became an unlikely winner of the race. He was a replacement driver who drove a year old racer which had become a show car.
Penske hired Al Unser, Sr. in 1983. Unser came close to winning his fourth Indianapolis 500 that year. He and Tom Sneva battled for the win. The crucial point in the race was on lap 172 (out of 200) when both men pitted for tires. Unser chose not to have the tires on his racer replaced and roared out of the pits after a 11.4 second pit stop. Sneva’s pitstop was longer—27.2 seconds—as his team changed the tires in addition to fuel. As the race wore down, Sneva, with fresh tires, started steadily gaining on Unser. Sneva passed Unser on lap 191 and went on to win by 11 seconds. Unser won just one race that season but gave Penske his third consecutive CART championship.
The next year wasn’t particularly good for Team Penske. While Unser’s teammate Rick Mears won the Indianapolis 500 from the pole, he was critically injured in a crash in September. Once again, Unser won one race. Mario Andretti won the CART championship after winning six of the sixteen races. At the end of the season, Penske decided to not renew Unser’s contract for 1985. Instead, he hired Danny Sullivan explaining that for the long term, he thought a younger driver was better for the team.
As fate would have it, Mears’ recovery from both of his feet being crushed was slow. Afraid that if Mears tried to race on the road courses would reinjure his feet, Penske hired Al Unser, Sr. to fill in on the road course races. While teammate Danny Sullivan won the Indianapolis 500 and the Miami finale, Unser’s sole victory in the Phoenix race resulted in him winning the drivers’ championship over his son, Al Unser, Sr. by one point.
Once again, at the end of the season, Penske chose to go with a younger line-up for the 1986 season. He offered Al Unser, Sr. a seat for the three 500-mile races. The team had a new chassis/engine combination, but it was a disappointment. Only Danny Sullivan finished at the top of the podium on two occasions. The one bright spot was the new car driven by Rick Mears showed its power and set a U. S. national closed course speed record.
For the 1987 season, Unser was without a ride. Team Penske included Danny Sullivan, Rick Mears and Danny Ongais. The team was not competitive in the first two races. While practicing at Indianapolis, Ongais suffered a concussion after crashing. Penske called Unser, Sr. to take Ongais’ seat for the race. The team had difficulty in getting up to speed during practice. Penske made the decision to bring out the year-old 1986 March in which Mears had set the speed record. In that car, Mears qualified third.
Penske also decided to bring out two other cars for Sullivan and Unser. Sullivan’s car had been sent to London, England for a racing car show. Team Penske mechanics had to convert the car from a Cosworth engine to a Chevrolet engine. Unser’s car had also been converted to a show car and was on loan to Hertz. The suspension had been chromed and it had a dummy engine. Eighteen crew members went back to team headquarters in Reading, Pennsylvania after the first weekend of qualifications to get the cars ready. Chief mechanic Derrick Walker said that they had to “beg, borrow, and steal parts and wheels to build up those two cars.” The effort paid off. Sullivan qualified on the sixth row while Unser qualified a row back.
On race day, the car to beat was driven by Mario Andretti who had taken the pole. Andretti was in control of the race when on the 177th lap, his engine backfired. He finished 180 of the laps for a ninth-place after leading for 170 laps. Al Unser, Sr. took the lead from Roberto Guerrero on lap 183 and won the race by 4.496 seconds.
The car that Unser drove was the Cummins/Holset Turbo. Cummins had entered the race four previous times (1931, 1934, 1950 and 1952) with diesel powered cars. Cummins purchased Holset Engineering Co., Ltd. in 1973.