Until 1978 all B&W engines operated on the impulse turbocharging system (Figure 13.2), but the search for enhanced economy in the wake of contemporary fuel crises dictated a change to the constant pressure system, yielding a saving of around 5 per cent in specific fuel consumption (Figure 13.3). In the years before its takeover by MAN of Germany in 1980, B&W introduced a number of engine series successively the K-GF, L-GF, L-GFCA and L-GB programme-before launching the current MC design portfolio now developed and m under the MAN B&W Diesel banner (see Chapter 10).