Do you mean the five BMW M1 racers that competed at Kyalami in 1979?
If so, they were early versions from the Procar series.
Here are the five teams.
Kyalami 1000km
Kelleners / Keizan - Eggenberger 1st 1st
Stuck / Winkelhock - Manfred Cassani 2nd 2nd
Mass / Watson - Project Four 4th 4th
Surer / van Rooyen - Max Heidegger DNF -
Hottinger / Berger - Helmut Marko DNF -