The 1978 World Manufacturers' Championship was split into 2 divisions in anattempt to spice things up. BMW responded with a small fleet of atmospheric 320's, entered by country teams. Since Porsche retired from the championship themselves, it was left to the customer teams to bring yet another title to Stuttgart. Both Kremer and Loos responded and had entertaining fights all over the season, with the predictable outcome of Porsche claiming the outright title and BMW taking the 2-litre class, both without any serious opposition.
The FIA GT cup, a championship within a championship, was won by Porsche as well, of course.
1979 surely would be better, with BMW's M1 standing by? But BMW would have other plans with the M1.