Gridpedia banned Engine
Turbocharged engines banned
Only 3.5-litre naturally aspirated engines were permitted, a formula that ran until 1994. Source
2 changes recorded for 1989. 1989 standings · results · ← 1988 · 1990 →
Only 3.5-litre naturally aspirated engines were permitted, a formula that ran until 1994. Source
With 20 teams and 39 cars, a one-hour Friday pre-qualifying session cut the field to 30 for qualifying and 26 for the race. Source